Huge work; i'm too tired to write commit message for all of it. Pleez let me sleep acouple of hours. Made most tests work. Started SBC.

2025-11-04 02:54:59 +03:00 · 2020-03-18 07:00:12 +03:00
parent 7badd31e42
commit 27d951227d
51 changed files with 3004 additions and 717 deletions
--- a/.gitignore
+++ b/.gitignore
@@ -1,7 +1,8 @@
 old.c
 **.db
 **.log
-**.old
 **.pyc
+**.old
+**.bak
 **__pycache__
 **_config.py
--- a/.gitmodules
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "compilers/pyssembly/typeshed"]
+	path = compilers/pyssembly/typeshed
+	url = https://github.com/python/typeshed.git
--- a/SBC/builtins.c
+++ b/SBC/builtins.c
@@ -0,0 +1,50 @@
+#include <stdarg.h>
+#include <string.h>
+
+typedef struct atom {
+	enum {b, i8, u8, i16, u16, i32, u32, i64, u64, i128, u128} type;
+	union {
+		_Bool* b;
+		int8_t* i8;
+		uint8_t* u8;
+		int16_t* i16;
+		uint16_t* u16;
+		int32_t* i32;
+		uint32_t* u32;
+		int64_t* i64;
+		uint64_t* u64;
+		void* data;
+	};
+} atom_t;
+
+typedef atom_t (*builtin_function)(int nargs, atom_t args[nargs]);
+
+typedef struct builtin {
+	const char* name;
+	builtin_function fp;
+} builtin_t;
+
+
+/// XXX ///
+
+
+atom_t _builtin_println(int nargs, atom_t args[nargs]) {
+	static int res;
+	res = puts(args[0].data);
+	return (atom_t){i32, .i32 = &res};
+}
+
+
+/// XXX ///
+
+
+builtin_t builtins[] = {
+	{"println", _builtin_println},
+{NULL, NULL}};
+
+builtin_function get_builtin(const char* name) {
+	for (builtin_t* i = builtins; i->name != NULL; i++)
+		if (strcmp(i->name, name) == 0)
+			return i->fp;
+	return NULL;
+}
--- a/SBC/bytecode.md
+++ b/SBC/bytecode.md
@@ -6,9 +6,22 @@
 ### NOP
 0x00
 > Does nothing.
-### RET
+### END
 0x01
+> Closes previously opened block.
+### POP
+0x02
+> Drops `TOS`.
+### RET
+0x03
 > Returns `TOS` to caller.
+### BLTIN
+0x04
+> Reads string from the bytecode until null byte (max 255 bytes) and pushes builtin function with that name.
+### CODE
+0x05
+> Reads code from the bytecode until the corresponding `END` instruction and pushes a reference to it and then its length.
+> Opens a block.


 ## Unary
@@ -44,7 +57,7 @@
 0x19
 > Pushes integer of smallest possible width equal to rounded `TOS`.
 ### CTOS
-0x1a
+0x1A
 > Pushes string consisting of char `TOS` and a null byte.


@@ -62,7 +75,7 @@
 ### DIV
 0x23
 > Pushes `TOS1 / TOS`.
-### FLRDIV
+### IDIV
 0x24
 > Pushes `TOS1 // TOS`.
 ### MOD
@@ -71,46 +84,88 @@
 ### POW
 0x26
 > Pushes `TOS1 ** TOS`.
-### SHL
+### LSH
 0x27
 > Pushes `TOS1 << TOS`.
-### SHR
+### RSH
 0x28
 > Pushes `TOS1 >> TOS`.
 ### AND
 0x29
 > Pushes `TOS1 & TOS`.
 ### OR
-0x2a
+0x2A
 > Pushes `TOS1 | TOS`.
 ### XOR
-0x2b
+0x2B
 > Pushes `TOS1 ^ TOS`.


+## Comparisons
+
+### EQ
+0x30
+> Pushes `TOS1 == TOS`.
+### NE
+0x31
+> Pushes `TOS1 != TOS`.
+### LT
+0x32
+> Pushes `TOS1 < TOS`.
+### GT
+0x33
+> Pushes `TOS1 > TOS`.
+### LE
+0x34
+> Pushes `TOS1 <= TOS`.
+### GE
+0x35
+> Pushes `TOS1 >= TOS`.
+### IS
+0x36
+> Pushes `TOS1 is TOS`.
+### ISNOT
+0x37
+> Pushes `TOS1 is not TOS`.
+
+
+## Flow control
+### IF
+0x40
+> If `TOS` is false, skips bytecode until corresponding `ELSE` (if exists) or `END`.
+> Opens a block.
+### ELSE
+0x41
+> Pops last `IF` result from `IF`-stack, and if it is true, skips bytecode to corresponding `END`.
+> Opens a block.
+### EXEC
+0x42
+> Executes code block `TOS1` of length `TOS` and pushes the result.
+
+
 ## With argument

 ### ALLOC*(bytes)*
-0xa0
+0xA0
 > Pushes reference to `calloc(1, bytes)`.
 ### EXTEND*(bytes)*
-0xa1
+0xA1
 > Extends integer `TOS` width to `bytes` bytes if narrower.
 ### CONST*(bytes)*
-0xa2
+0xA2
 > Reads next `bytes` bytes of bytecode and pushes a reference to a copy of them.
 ### JUMPF*(offset)*
-0xa3
+0xA3
 > Jumps `offset` bytes of bytecode forward.
 ### JUMPB*(offset)*
-0xa4
+0xA4
 > Jumps `offset` bytes of bytecode backward.
 ### SCPGET*(cell)*
-0xa5
+0xA5
 > Pushes the value of cell `cell` of local scope variables array.
 ### SCPSET*(cell)*
-0xa6
+0xA6
 > Sets the value of cell `cell` of local scope variables array to `TOS`.
 ### CALL*(nargs)*
-0xa7
-> Pops `nargs ^ (1 << 7)` TODO
+0xA7
+> Calls `TOS` with `nargs` arguments popped from stack (below the callable).
--- a/SBC/dissbc.py
+++ b/SBC/dissbc.py
@@ -0,0 +1,50 @@
+#!/usr/bin/python3
+# SBC Disassembler
+
+from utils.nolog import *
+
+opcodes = {int(m[2], 16): m[1] for m in re.finditer(r'### (\w+).*?\n(\w+)', open(os.path.join(os.path.dirname(sys.argv[0]), 'bytecode.md')).read())}
+HASARG = 0xa0
+
+def dissbc(code, no_opnames=False):
+	cp = 0
+	codesize = len(code)
+	blocklvl = 0
+	while (cp < codesize):
+		opcode = code[cp]; cp += 1
+		opname = opcodes.get(opcode)
+		if (opname == 'END'): blocklvl -= 1
+		print('\t'*blocklvl, end='')
+		if (opname is None): print("\033[2mUNKNOWN: %02x\033[0m" % opcode); continue
+		print(f"\033[1m0x{opcode:02x}{' '+opname if (not no_opnames) else ''}\033[0m", end='')
+		if (opcode > HASARG):
+			arg = code[cp]; cp += 1
+			print("(%d|0x%02x)" % (arg, arg), end='')
+
+		if (opname == 'CONST'):
+			const = code[cp:cp+arg]
+			cp += arg
+			print(':', '0x'+const.hex(), end='')
+			print(' |', str().join(chr(i) if (32 <= i < 128) else '.' for i in const), end='')
+		elif (opname == 'BLTIN'):
+			name = bytearray()
+			while (code[cp] != 0):
+				name.append(code[cp]); cp += 1
+			else: cp += 1
+			print(':', name.decode('ascii'), end='')
+
+		if (opname in ('IF', 'ELSE', 'CODE')):
+			print(':', end='')
+			blocklvl += 1
+
+		print()
+
+@apmain
+@aparg('file', metavar='<file.sbc>')
+@aparg('--no-opnames', action='store_true')
+def main(cargs):
+	dissbc(open(cargs.file, 'rb').read(), no_opnames=cargs.no_opnames)
+
+if (__name__ == '__main__'): exit(main(nolog=True), nolog=True)
+
+# by Sdore, 2020
--- a/SBC/sbc
+++ b/SBC/sbc
--- a/SBC/sbc.c
+++ b/SBC/sbc.c
@@ -0,0 +1,217 @@
+// SBC
+
+#define _GNU_SOURCE
+#include <ctype.h>
+#include <stdio.h>
+#include <assert.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include "builtins.c"
+#include "stack.c"
+
+typedef uint8_t code_t;
+
+enum {
+	// Standalone
+	NOP	= 0x00,
+	END	= 0x01,
+	POP	= 0x02,
+	RET	= 0x03,
+	BLTIN	= 0x04,
+	CODE	= 0x05,
+
+	// Unary
+	POS	= 0x10,
+	NEG	= 0x11,
+	NOT	= 0x12,
+	INV	= 0x13,
+	ATOI	= 0x14,
+	ITOA	= 0x15,
+	ITOF	= 0x16,
+	CEIL	= 0x17,
+	FLR	= 0x18,
+	RND	= 0x19,
+	CTOS	= 0x1A,
+
+	// Binary
+	ADD	= 0x20,
+	SUB	= 0x21,
+	MUL	= 0x22,
+	DIV	= 0x23,
+	IDIV	= 0x24,
+	MOD	= 0x25,
+	POW	= 0x26,
+	SHL	= 0x27,
+	SHR	= 0x28,
+	AND	= 0x29,
+	OR	= 0x2A,
+	XOR	= 0x2B,
+
+	// Comparisons
+	EQ	= 0x30,
+	NE	= 0x31,
+	LT	= 0x32,
+	GT	= 0x33,
+	LE	= 0x34,
+	GE	= 0x35,
+	IS	= 0x36,
+	ISNOT	= 0x37,
+
+	// Flow control
+	IF	= 0x40,
+	ELSE	= 0x41,
+	EXEC	= 0x42,
+
+	// With argument
+	ALLOC	= 0xA0,
+	EXTEND	= 0xA1,
+	CONST	= 0xA2,
+	JUMPF	= 0xA3,
+	JUMPB	= 0xA4,
+	SCPGET	= 0xA5,
+	SCPSET	= 0xA6,
+	CALL	= 0xA7,
+
+	HASARG	= 0xA0,
+};
+
+atom_t exec(code_t* code, uint32_t codesize) { // TODO: freeing
+	stack_t* st = stack();
+	atom_t scp[255]; // TODO
+	code_t* cb[255]; // TODO
+	uint32_t cbi = 0;
+
+	uint32_t cp = 0;
+	while (cp < codesize) {
+		code_t opcode = code[cp++];
+		uint32_t ocp = cp;
+
+		switch (opcode) {
+			// Standalone
+			case NOP: break;
+			case END: break;
+			case POP: stack_pop(st); break;
+			case RET: return st->top->data;
+			case BLTIN: {
+				char name[256];
+				strncpy(name, (char*)code+cp, 255);
+				while (code[cp++] != '\0');
+				stack_push(st, (atom_t){.data = get_builtin(name)});
+			}; break;
+			case CODE: {
+				code_t* code_block = malloc(codesize);
+				static uint32_t cbp = 0;
+				uint32_t blocklvl = 1;
+				while (cp < codesize) {
+					code_t c = code[cp++];
+					if (c == CODE	||
+					    c == IF	||
+					    c == ELSE) blocklvl++;
+					else if (c == END) blocklvl--;
+					if (blocklvl <= 0) break;
+					code_block[cbp++] = c;
+					if (c > HASARG) code_block[cbp++] = code[cp++];
+					if (c == CONST)
+						for (uint8_t i = code_block[cbp-1]; i > 0; i--)
+							code_block[cbp++] = code[cp++];
+					else if (c == BLTIN)
+						do code_block[cbp++] = code[cp++];
+						while (code[cp-1] != '\0');
+				}
+				cb[cbi++] = realloc(code_block, cbp);
+				free(code_block);
+				stack_push(st, (atom_t){u32, .u32 = &cbp});
+				stack_push(st, (atom_t){.data = &cb[cbi-1]});
+			}; break;
+
+			// Unary
+			case POS: *st->top->data.i32 = abs(*st->top->data.i32); break;
+			case ITOA: {
+				char s[12];
+				fprintf(stderr, "-- %x\n", *st->top->data.i32);
+				snprintf(s, sizeof(s)/sizeof(*s), "%d", *st->top->data.i32);
+				st->top->data.data = strdup(s);
+			}; break;
+
+			// Binary (TODO)
+			case ADD: *st->top->data.i32 += *stack_pop(st).i32; break;
+			case SUB: *st->top->data.i32 -= *stack_pop(st).i32; break;
+
+			// Comparisons
+			case LT: *st->top->data.b = *stack_pop(st).i32 > *st->top->data.i32; break;
+
+			// Flow control
+			case EXEC: {
+				uint32_t exec_codesize = *stack_pop(st).u32;
+				code_t* exec_code = stack_pop(st).data;
+				stack_push(st, exec(exec_code, exec_codesize));
+			}; break;
+
+			// With argument
+			case CONST: {
+				uint8_t len = code[cp++];
+				stack_push(st, (atom_t){.data = memcpy(malloc(len), code+cp, len)});
+				fprintf(stderr, "-- l=%02x: %x\n", len, *st->top->data.i32);
+				cp += len;
+			}; break;
+			case SCPGET: {
+				uint8_t cell = code[cp++];
+				stack_push(st, scp[cell]);
+			}; break;
+			case SCPSET: {
+				uint8_t cell = code[cp++];
+				scp[cell] = stack_pop(st);
+				fprintf(stderr, "-- c%d = %d\n", cell, *scp[cell].i32);
+			}; break;
+			case CALL: {
+				uint8_t nargs = code[cp++];
+				fprintf(stderr, "-- nargs=%d\n", nargs);
+				builtin_function func = stack_pop(st).data;
+				atom_t args[nargs];
+				for (uint8_t i = 0; i < nargs; i++)
+					args[i] = stack_pop(st);
+				stack_push(st, func(nargs, args));
+			}; break;
+
+			default: fprintf(stderr, "Not Implemented opcode: 0x%02x\n", opcode); exit(3);
+		}
+
+		fprintf(stderr, "[%02x", opcode);
+		if (opcode > HASARG) fprintf(stderr, "(%d|0x%02x)", code[ocp], code[ocp++]);
+		fputc(':', stderr);
+		do fprintf(stderr, " %02x", code[ocp++]);
+		while (ocp < cp && ocp < codesize);
+		if (st->top != NULL) {
+			fprintf(stderr, ", TOS = %u(0x%02x)", *st->top->data.i32, *st->top->data.i32);
+			if (isprint(*(char*)st->top->data.data)) {
+				fprintf(stderr, " | ");
+				for (char* p = st->top->data.data; *p != '\0'; p++)
+					fputc(isprint(*p)?*p:'.', stderr);
+			}
+		}
+		fprintf(stderr, "]\n");
+	}
+
+	return (atom_t){.data = NULL};
+}
+
+int main(int argc, char* argv[]) {
+	if (argc != 2) {
+		fprintf(stderr, "Usage: %s <file.sbc>\n", basename(argv[0]));
+		exit(1);
+	}
+
+	FILE* fd = fopen(argv[1], "rb");
+	fseek(fd, 0, SEEK_END);
+	long fsize = ftell(fd);
+	fseek(fd, 0, SEEK_SET);
+
+	code_t code[fsize];
+	fread(code, sizeof(*code), fsize, fd);
+	fclose(fd);
+
+	exec(code, fsize);
+}
+
+// by Sdore, 2020
--- a/SBC/stack.c
+++ b/SBC/stack.c
@@ -0,0 +1,53 @@
+/*
+#define CAT(a, b) a##_##b
+#define TEMPLATE(name, type) CAT(name, type)
+
+#define stack		TEMPLATE(stack, T)
+#define stack_t	TEMPLATE(stack_t, T)
+#define stack_item	TEMPLATE(stack_item, T)
+#define stack_push	TEMPLATE(stack_push, T)
+#define stack_pop	TEMPLATE(stack_pop, T)
+*/
+
+#define T atom_t
+
+typedef struct stack {
+	struct stack_item* top;
+} stack_t;
+
+struct stack_item {
+	T data;
+	struct stack_item* below;
+};
+
+stack_t* stack() {
+	stack_t* st = malloc(sizeof(*st));
+	st->top = NULL;
+	return st;
+}
+
+void stack_push(stack_t* st, T data) {
+	struct stack_item* new = malloc(sizeof(*new));
+	new->data = data;
+	if (st->top != NULL) new->below = st->top;
+	st->top = new;
+}
+
+T stack_pop(stack_t* st) {
+	assert (st->top != NULL);
+	struct stack_item* item = st->top;
+	st->top = item->below;
+	T data = item->data;
+	free(item);
+	return data;
+}
+
+/*
+#undef stack
+#undef stack_t
+#undef stack_item
+#undef stack_push
+#undef stack_pop
+*/
+
+#undef T
--- a/SBC/tests/hw.sbc
+++ b/SBC/tests/hw.sbc
--- a/Slang.md
+++ b/Slang.md
@@ -18,19 +18,17 @@ char f(str x) {  # f() is of type char, x is of type str
 	return c
 }

-char g(str x) {  # g() is of type char, x is of type str
+auto g(str x) {  # g() is of type char, x is of type str
 	return x[0]  # retval is of type char
 }

 int h(int x) = x+1  # h() is of type int, x is of type int

-void main() {
-	print(h(n), \
+main {
+	stdio.println(h(n), \  # comment here too
 		f('123asd') + g('32') + 1)  #--> «123124 f»
-	print(q/z/2**96)  #--> «4294967296.0»
+	stdio.println(q/z/2**96)  #--> «4294967296.0»
 }
-
-main()
 ```

 ## Tokens
@@ -83,6 +81,7 @@ _Note: `*` after syntax unit means any number of them._
 * `<exprkeyword> [expr]` — `keywordexpr` (keyword expression)
 * `<typedef> <identifier> [= <value>]` — `vardef` (variable definition)
 * `<identifier> = <value>` — `assignment`
+* `<identifier>[, <identifier>]* = <value>` — `unpackassignment`
 * `<value>([<callargs> | <callkwargs> | <callargs>, <callkwargs>])` — `funccall` (function call)
 * `<expr>` — expr evaluation (only in REPL)
 * `if (<expr>) <block>` — `conditional`
@@ -106,7 +105,7 @@ _Note: `*` after syntax unit means any number of them._

 Non-empty sequence of alphanumeric characters plus underscore («_»), not starting with a digit character.

-Regex: `[_\w]+[_\w\d]*`
+Regex: `[_\w][_\w\d]*`

 ### Data types

@@ -133,6 +132,12 @@ _Note: `*` after syntax unit here means any number of them, `+` means at least o
 * `<<0<b | o | x>><digit+> | <digit+>.<digit*> | <digit*>.<digit+>>` — number
 * `<"<character*>" | '<character*>'>` — string

+### Literal structures
+
+* `[ <value>[, <value>]* ]` — list
+* `( [type] <value>[, [type] <value>]* )` — tuple
+* `{ <<key>: <value>>* }` — map
+
 ## Operators

 * `<operator> <operand>` — unary operators usage
@@ -143,7 +148,7 @@ _Note: `*` after syntax unit here means any number of them, `+` means at least o

 A set of pre-defined character operators:

-* `!$%&*+-:^~` — unary charset
+* `!+-~` — unary charset
 * `%&*+-/<=>^|` — binary charset
 * `==`, `**`, `//`, `<<`, `>>` — double-char binary operators

@@ -167,4 +172,4 @@ A set of pre-defined keyword operators:
 All character class checks are performed in current locale.

 ---
-_by Sdore, 2019_
+_by Sdore, 2020_
--- a/Slang.py
+++ b/Slang.py
@@ -2,12 +2,10 @@
 # Slang

 from .ast import *
-from .repl import *
 from .compilers import *
-from .compilers.pyssembly import *
 from utils.nolog import *; logstart('Slang')

-def debug_compile(src, filename='<string>'):
+def compile(src, filename='<string>', *, compiler):
 	try:
 		#print(f"Source: {{\n{S(src).indent()}\n}}\n")

@@ -15,46 +13,36 @@ def debug_compile(src, filename='<string>'):
 		#print(f"Tokens:\n{pformat(tl)}\n")

 		ast = build_ast(tl, filename)
-		#print(f"Code: {repr(ast.code)}\n")
+		#print(f"Code: {ast.code}\n")

 		#print(f"Nodes: {pformat(list(walk_ast_nodes(ast)))}\n")

 		optimize_ast(ast, validate_ast(ast))
-		#print(f"Optimized: {repr(ast.code)}\n")
+		#print(f"Optimized: {ast.code}\n")

-		code = PyssemblyCompiler.compile_ast(ast, validate_ast(ast), filename=filename)
+		code = compiler.compile_ast(ast, validate_ast(ast), filename=filename)
 		#print("Compiled.\n")
-
-		#print("Running.\n")
-		#exec(code, {})
-		#print("\nFinished.\n")
 	except (SlSyntaxError, SlValidationError, SlCompilationError) as ex:
-		ex.line = src.split('\n')[ex.lineno-1]
+		if (not ex.line): ex.line = src.split('\n')[ex.lineno-1]
 		sys.exit(ex)
-	except pyssembly.PyssemblyError as ex:
-		print('Error:', ex)
-		try: code = ex.code.to_code()
-		except pyssembly.PyssemblyError: pass
-		else:
-			print("\nHere is full pyssembly code 'til the errorneous line:\n")
-			dis.dis(code)
-		sys.exit(1)
-	else: return code
+	return code

+@apmain
+@aparg('file', metavar='<file>', type=argparse.FileType('r'))
+@aparg('-o', dest='output')
+@aparg('-f', dest='compiler', required=True)
 def main(cargs):
-	if (cargs.o is None and not cargs.file.name.rpartition('.')[0]):
-		argparser.add_argument('-o', metavar='<output>', required=True)
+	if (cargs.output is None and not cargs.file.name.rpartition('.')[0]):
+		argparser.add_argument('-o', dest='output', required=True)
 		cargs = argparser.parse_args()
 	src = cargs.file.read()
 	filename = cargs.file.name
-	code = debug_compile(src, filename=filename.join('""'))
-	open(cargs.o or cargs.file.name.rpartition('.')[0]+'.pyc', 'wb').write(pyssembly.asm(code))
+	_cns = importlib.import_module('.compilers.'+cargs.compiler, package=__package__).__dict__.values()
+	compiler = first(i for i in allsubclasses(Compiler) if i in _cns)
+	code = compile(src, filename=filename.join('""'), compiler=compiler)
+	open(cargs.output or cargs.file.name.rpartition('.')[0]+compiler.ext, 'wb').write(code)

-if (__name__ == '__main__'):
-	argparser.add_argument('file', metavar='<file>', type=argparse.FileType('r'))
-	argparser.add_argument('-o', metavar='<output>')
-	cargs = argparser.parse_args()
-	logstarted(); exit(main(cargs))
+if (__name__ == '__main__'): exit(main())
 else: logimported()

-# by Sdore, 2019
+# by Sdore, 2020
--- a/TODO.md
+++ b/TODO.md
@@ -1 +1,14 @@
- arrays
+- doc `import [[<namespace>:][<path>/]<pkg>:]<name>`
+- allow `?` modifier only if ≥2 args ?
+- https://esolangs.org/wiki/Stlang
+- https://esolangs.org/wiki/Object_disoriented
+- https://esolangs.org/wiki/Funciton ?
+- `O.each { code }` (i.e. `O.each({code})`)
+- Proposal: `if`, `for` and `while` without brackets
+- OOP
+- Increments
+- FIXME: whitespace in srclength
+- renew all `__repr__`s *AND* `__str__`s
+- Proposal: `f(kw: arg)` = `f(kw=arg)`
+- Proposal: [https://docs.microsoft.com/ru-ru/dotnet/csharp/language-reference/operators/default]
+- FIXME: `auto' rettype
--- a/asm/hw
+++ b/asm/hw
--- a/asm/hw.asm
+++ b/asm/hw.asm
@@ -0,0 +1,16 @@
+bits 64
+
+;section	.rodata
+hw: db "hw", 0
+
+.text
+global _start
+extern puts
+_start:
+	push	rbp
+	mov	rbp, rsp
+	lea	rdi, [hw+rip]
+	call	puts
+	mov	rax, 0
+	pop	rbp
+	ret
--- a/asm/hw.c
+++ b/asm/hw.c
@@ -0,0 +1 @@
+main() {puts("hw");}
--- a/asm/hw.o
+++ b/asm/hw.o
--- a/ast.py
+++ b/ast.py
--- a/compilers/init.py
+++ b/compilers/init.py
@@ -1,7 +1,8 @@
 #!/usr/bin/python3
 # Slang compilers

-import abc
+from ..ast import SlSyntaxError, SlValidationError
+import abc, traceback

 class Compiler(abc.ABC):
 	@abc.abstractclassmethod
@@ -23,9 +24,10 @@ class SlCompilationError(Exception):
 	def __str__(self):
 		l, line = lstripcount(self.line.partition('\n')[0].replace('\t', ' '), ' \t')
 		offset = (self.node.offset-l) if (self.node.offset != -1) else len(line)
-		return (f'\033[2m(in {self.scope})\033[0m ' if (self.scope is not None) else '')+f"Compilation error: {self.desc}{self.at}"+(':\n'+\
-			'  \033[1m'+line[:offset]+'\033[91m'+line[offset:]+'\033[0m\n'+\
-			'  '+' '*offset+'\033[95m^'+'~'*(self.node.length-1) if (line) else '')
+		return (f'\033[2m(in {self.scope})\033[0m ' if (self.scope is not None) else '') + f"Compilation error: {self.desc}{self.at}"+(':\n' + \
+			'  \033[1m'+line[:offset]+'\033[91m'+line[offset:]+'\033[0m\n' + \
+			'  '+' '*offset+'\033[95m^'+'~'*(self.node.length-1)+'\033[0m' if (line) else '') + \
+			(f"\n\n\033[1;95mCaused by:\033[0m\n{self.__cause__ if (isinstance(self.__cause__, (SlSyntaxError, SlValidationError, SlCompilationError))) else ' '+str().join(traceback.format_exception(type(self.__cause__), self.__cause__, self.__cause__.__traceback__))}" if (self.__cause__ is not None) else '')

 	@property
 	def at(self):
--- a/compilers/esolang/gibberish.py
+++ b/compilers/esolang/gibberish.py
@@ -0,0 +1,135 @@
+#!/usr/bin/python3
+# Slang Esolang Gibberish compilation target (PoC)
+# https://esolangs.org/wiki/Gibberish_(programming_language)
+
+from .. import *
+from Slang.ast import *
+from utils import *
+
+class Instrs:
+	binopmap = {
+		'+': b'ea',
+		'-': b'es',
+		'*': b'em',
+		'/': b'ed',
+		'<<': b'fl',
+		'>>': b'fr',
+		'&': b'ga',
+	}
+
+	@init_defaults
+	@autocast
+	def __init__(self, ns, stack: Slist, functions: dict):
+		self.ns, self.stack, self.functions = ns, stack, functions
+		self.code = bytearray()
+
+	@dispatch
+	def add(self, x: ASTRootNode):
+		self.add(x.code)
+
+	@dispatch
+	def add(self, x: ASTCodeNode):
+		for i in x.nodes:
+			self.add(i)
+
+	@dispatch
+	def add(self, x: ASTVardefNode):
+		if (x.value is not None):
+			self.load(x.value)
+			self.stack[-1] = Signature.build(x, self.ns)
+
+	@dispatch
+	def add(self, x: ASTAssignmentNode):
+		sig = Signature.build(x.name, self.ns)
+		for ii, i in enumerate(self.stack):
+			if (i == sig): self.stack[ii] = None
+		self.load(x.value)
+		self.stack[-1] = sig
+
+	@dispatch
+	def add(self, x: ASTFunccallNode):
+		self.load(x)
+		self.code += b'ev'
+		self.stack.pop()
+
+	@dispatch
+	def add(self, x: ASTFuncdefNode):
+		code_ns = self.ns.derive(x.name.identifier)
+		if (x.name.identifier == 'main'):
+			assert not x.argdefs
+			name = x.name.identifier
+		else: name = f"{x.name.identifier}__{self.ns.signatures[x.name.identifier].call.index(CallArguments(args=tuple(Signature.build(i, code_ns) for i in x.argdefs)))}"
+		f_instrs = Instrs(ns=code_ns, stack=(Signature.build(i, code_ns) for i in x.argdefs), functions=self.functions.copy())
+		f_instrs.add(x.code)
+		#dlog(f"{x.__fsig__()} instrs:\n"+'\n'.join(f_instrs.instrs)+'\n')
+		self.functions[name] = f_instrs
+
+	@dispatch
+	def add(self, x: ASTKeywordExprNode):
+		if (x.keyword.keyword == 'return'):
+			self.load(x.value)
+		else: raise NotImplementedError(x.keyword)
+
+	@dispatch
+	def load(self, x: ASTLiteralNode):
+		s = str(eval(str(x.literal))).encode().split(b']')
+		if (s):
+			s[0] = b'['+s[0]
+			s[-1] += b']'
+		self.code += b'][93]eigtec['.join(s) + b'c'*(len(s)-1)
+		if (issubclass(literal_type(x.literal), (int, float))): self.code += b'ei'
+		self.stack.append(None)
+
+	@dispatch
+	def load(self, x: ASTIdentifierNode):
+		dlog(self.stack)
+		sig = Signature.build(x, self.ns)
+		i = self.stack.rindex(sig)
+		self.code += (b'[%d]eip' if (i >= 10) else b'%dep') % i
+		self.stack.append(sig)
+
+	@dispatch
+	def load(self, x: ASTValueNode):
+		self.load(x.value)
+
+	@dispatch
+	def load(self, x: ASTFunccallNode):
+		assert not (x.callargs.starargs or x.callkwargs.callkwargs or x.callkwargs.starkwargs)
+		if (x.callable.value.identifier == 'print'):
+			for i in x.callargs.callargs[:-1]:
+				self.load(i)
+				self.code += b'eq[32]eigteq'
+				self.stack.pop()
+			if (x.callargs.callargs):
+				self.load(x.callargs.callargs[-1])
+				self.stack.pop()
+			else: self.code += b'[]'
+			self.code += b'eo'
+			self.stack.append(None)
+			return
+		for i in x.callargs.callargs[::-1]:
+			self.load(i)
+			self.stack.pop()
+		self.code += self.functions[f"{x.callable.value.identifier}__{self.ns.signatures[x.callable.value.identifier].call.index(CallArguments.build(x, self.ns))}" if (isinstance(x.callable, ASTValueNode) and isinstance(x.callable.value, ASTIdentifierNode) and x.callable.value.identifier in self.ns.signatures) else x.callable.value.identifier].code#.join((b'{', b'}'))
+
+	@dispatch
+	def load(self, x: ASTBinaryExprNode):
+		self.load(x.lvalue)
+		self.load(x.rvalue)
+		self.code += self.binopmap[x.operator.operator]
+		self.stack.pop()
+		self.stack.pop()
+		self.stack.append(None)
+
+class GibberishCompiler(Compiler):
+	ext = '.gib'
+
+	@classmethod
+	def compile_ast(cls, ast, ns, *, filename):
+		instrs = Instrs(ns=ns)
+		instrs.add(ast)
+		code = bytes(instrs.code)
+		dlog("Code:\n"+code.decode())
+		return code
+
+# by Sdore, 2019
--- a/compilers/pyssembly.py
+++ b/compilers/pyssembly.py
@@ -1,278 +0,0 @@
-#!/usr/bin/python3
-# Slang Pyssembly compiler target
-
-import pyssembly
-from . import *
-from Slang.ast import *
-from utils import *
-
-class Instrs:
-	unopmap = {
-		'+': 'POS',
-		'-': 'NEG',
-		'!': 'NOT',
-		'~': 'INV',
-		'not': 'NOT',
-	}
-
-	binopmap = {
-		'+': 'ADD',
-		'-': 'SUB',
-		'*': 'MUL',
-		'/': 'DIV',
-		'//': 'FLOORDIV',
-		'%': 'MOD',
-		'**': 'POW',
-		'<<': 'LSHIFT',
-		'>>': 'RSHIFT',
-		'&': 'AND',
-		'|': 'OR',
-		'^': 'XOR',
-		'and': 'AND',
-		'or': 'OR',
-	}
-
-	@init_defaults
-	def __init__(self, *, name, ns, filename, argdefs=()):
-		self.name, self.ns, self.filename = name, ns, filename
-		self.instrs = list()
-		self.consts = list()
-		self.argnames = list()
-		for i in argdefs:
-			if (i.modifier is not None): raise SlCompilationError("argument modifiers are not supported yet", i.modifier)
-			self.argnames.append(i.name.identifier)
-		self.cellvars = self.argnames.copy()
-		self.srclnotab = list()
-
-	def compile(self):
-		return pyssembly.Code('\n'.join(self.instrs), name=self.name, filename=self.filename.strip('"'), srclnotab=self.srclnotab, consts=self.consts, argnames=self.argnames)
-
-	@dispatch
-	def add(self, x: ASTRootNode):
-		self.add(x.code)
-
-	@dispatch
-	def add(self, x: ASTCodeNode):
-		lastln = int()
-		for i in x.nodes:
-			self.srclnotab.append(i.lineno-lastln)
-			lastln = i.lineno
-			l = len(self.instrs)
-			self.add(i)
-			self.srclnotab += [0]*(len(self.instrs)-l-1)
-
-	@dispatch
-	def add(self, x: ASTValueNode):
-		self.add(x.value)
-
-	@dispatch
-	def add(self, x: ASTVardefNode):
-		if (x.value is not None):
-			self.load(x.value)
-			self.store(x.name)
-
-	@dispatch
-	def add(self, x: ASTAssignmentNode):
-		if (x.inplace_operator is not None): self.instrs.append(f"LOAD	({x.name})")
-		self.load(x.value)
-		if (x.inplace_operator is not None): self.instrs.append(f"INP_{self.binopmap[x.inplace_operator.operator]}")
-		self.store(x.name)
-
-	@dispatch
-	def add(self, x: ASTFunccallNode):
-		self.load(x)
-		self.instrs.append("POP")
-
-	@dispatch
-	def add(self, x: ASTBlockNode):
-		self.add(x.code)
-
-	@dispatch
-	def add(self, x: ASTFuncdefNode):
-		code_ns = self.ns.derive(x.name.identifier)
-		name = f"{x.name.identifier}__{self.ns.signatures[x.name.identifier].call.index(CallArguments(args=tuple(Signature.build(i, code_ns) for i in x.argdefs)))}"
-		f_instrs = Instrs(name=f"{self.name}.{name}", ns=code_ns, filename=self.filename, argdefs=x.argdefs)
-		f_instrs.add(x.code)
-		#dlog(f"{x.__fsig__()} instrs:\n"+'\n'.join(f_instrs.instrs)+'\n')
-		self.consts.append(f_instrs.compile().to_code())
-		self.instrs += [
-			f"LOAD	{len(self.consts)-1}",
-			f"LOAD	('{self.name}.{name}')",
-			f"MAKE_FUNCTION	0", # TODO: flags
-		]
-		self.store(name)
-
-	@dispatch
-	def add(self, x: ASTKeywordExprNode):
-		if (x.keyword.keyword == 'import'):
-			ns, _, name = x.value.identifier.partition('::')
-			assert ns == 'py'
-			self.instrs += [
-				"LOAD	(0)", # TODO
-				"LOAD	(None)", # TODO
-			]
-			self.instrs.append(f"IMPORT_NAME	({name})")
-			self.store(name)
-		elif (x.keyword.keyword == 'return'):
-			self.load(x.value)
-			self.instrs.append("RET")
-		else: raise NotImplementedError(x.keyword)
-
-	@dispatch
-	def add(self, x: ASTConditionalNode):
-		self.load(x.condition)
-		self.instrs.append("JPOPF	:else")
-		self.add(x.code)
-		self.instrs += [
-			"JUMPF	:end",
-			":else",
-			":end",
-		]
-
-	@dispatch
-	def add(self, x: ASTForLoopNode):
-		self.load(x.iterable)
-		#self.cellvars.append(x.name.identifier) # TODO FIXME
-		self.instrs += [
-			"SETUP_LOOP	:end",
-			"ITER",
-			":for",
-			"FOR	:else",
-		]
-		self.store(x.name)
-		self.add(x.code)
-		self.instrs += [
-			"JUMPA	:for",
-			":else",
-			"POP_BLOCK",
-			":end",
-		]
-
-	@dispatch
-	def add(self, x: ASTWhileLoopNode):
-		self.instrs += [
-			"SETUP_LOOP	:end",
-			":while",
-		]
-		self.load(x.condition)
-		self.instrs.append("JPOPF	:else")
-		self.add(x.code)
-		self.instrs += [
-			"JUMPA	:while",
-			":else",
-			"POP_BLOCK",
-			":end",
-		]
-
-	@dispatch
-	def add(self, x: ASTElseClauseNode):
-		assert (self.instrs[-1] == ":end")
-		popped = [self.instrs.pop()]
-		if (self.instrs[-1] == "POP_BLOCK"): popped.append(self.instrs.pop())
-		self.add(x.code)
-		self.instrs += reversed(popped)
-
-	@dispatch
-	def load(self, x: ASTLiteralNode):
-		self.instrs.append(f"LOAD	({x.literal})")
-
-	@dispatch
-	def load(self, x: ASTIdentifierNode):
-		self.load(x.identifier)
-
-	@dispatch
-	def load(self, x: ASTValueNode):
-		self.load(x.value)
-
-	@dispatch
-	def load(self, x: ASTFunccallNode):
-		if (isinstance(x.callable, ASTValueNode) and isinstance(x.callable.value, ASTIdentifierNode) and x.callable.value.identifier in self.ns.signatures):
-			self.load(f"{x.callable.value.identifier}__{self.ns.signatures[x.callable.value.identifier].call.index(CallArguments.build(x, self.ns))}")
-		else: self.load(x.callable)
-		n = int()
-
-		for i in x.callargs.callargs:
-			self.load(i)
-			n += 1
-		if (x.callargs.starargs):
-			if (n):
-				self.instrs.append(f"BUILD_TUPLE	{n}")
-				n = 1
-			for i in x.callargs.starargs:
-				self.load(i)
-				n += 1
-			self.instrs.append(f"BUILD_TUPLE_UNPACK_WITH_CALL	{n}")
-			n = 0
-
-		for i in x.callkwargs.callkwargs:
-			self.load(f"'{i[0]}'")
-			self.load(i[1])
-			n += 1
-		if (n and (x.callargs.starargs or x.callkwargs.starkwargs)):
-			self.instrs.append(f"BUILD_MAP	{n}")
-			n = 1
-		if (x.callkwargs.starkwargs):
-			for i in x.callkwargs.starkwargs:
-				self.load(i)
-				n += 1
-			self.instrs.append(f"BUILD_MAP_UNPACK_WITH_CALL	{n}")
-			n = 1
-
-		self.instrs.append(f"CALL{'EX' if (x.callargs.starargs or x.callkwargs.starkwargs) else 'KW' if (x.callkwargs.callkwargs) else ''}	{n}")
-
-	@dispatch
-	def load(self, x: ASTAttrgetNode):
-		self.load(x.value)
-		assert x.optype.special == '.' # TODO
-		self.instrs.append(f"GETATTR	({x.attr})")
-
-	@dispatch
-	def load(self, x: ASTUnaryExprNode):
-		self.load(x.value)
-		self.instrs.append(self.unopmap[x.operator.operator])
-
-	@dispatch
-	def load(self, x: ASTBinaryExprNode):
-		self.load(x.lvalue)
-		char = isinstance(Signature.build(x.lvalue, self.ns), stdlib.char)
-		if (char): self.instrs.append("CALL	(ord) 1")
-		if (x.operator.operator == 'xor'): self.instrs.append("BOOL")
-		self.load(x.rvalue)
-		if (char and isinstance(Signature.build(x.rvalue, self.ns), stdlib.char)): self.instrs.append("CALL	(ord) 1")
-		if (x.operator.operator == 'xor'): self.instrs.append("BOOL")
-		if (x.operator.operator == 'to'): self.instrs.append("CALL	(range) 2")
-		else: self.instrs.append(self.binopmap[x.operator.operator])
-		if (x.operator.operator == 'xor'): self.instrs.append("BOOL")
-		if (char and x.operator.operator not in keyword_operators): self.instrs.append("CALL	(chr) 1")
-
-	@dispatch
-	def load(self, x: ASTItemgetNode):
-		self.load(x.value)
-		self.load(x.key)
-		self.instrs.append("SUBSCR")
-
-	@dispatch
-	def load(self, x: str):
-		self.instrs.append(f"LOAD	{f'${x}' if (x in self.cellvars) else f'({x})'}")
-
-	@dispatch
-	def store(self, x: ASTIdentifierNode):
-		self.store(x.identifier)
-
-	@dispatch
-	def store(self, x: str):
-		self.instrs.append(f"STORE	{f'${x}' if (x in self.cellvars) else f'({x})'}")
-
-class PyssemblyCompiler(Compiler):
-	@classmethod
-	def compile_ast(cls, ast, ns, *, filename):
-		instrs = Instrs(name='<module>', ns=ns, filename=filename)
-		instrs.add(ast)
-		#dlog("Instrs:\n"+'\n'.join(instrs.instrs)+'\n')
-		code = instrs.compile().to_code()
-		#dis.show_code(code)
-		#dis.dis(code)
-		#print()
-		return code
-
-# by Sdore, 2019
--- a/compilers/pyssembly/init.py
+++ b/compilers/pyssembly/init.py
@@ -0,0 +1,486 @@
+#!/usr/bin/python3
+# Slang Pyssembly compiler target
+
+import pyssembly
+from . import std
+from .. import *
+from ...ast import *
+from utils import *
+
+class Instrs:
+	unopmap = {
+		'+': 'POS',
+		'-': 'NEG',
+		'!': 'NOT',
+		'~': 'INV',
+		'not': 'NOT',
+	}
+
+	binopmap = {
+		'+': 'ADD',
+		'-': 'SUB',
+		'*': 'MUL',
+		'/': 'DIV',
+		'//': 'IDIV',
+		'%': 'MOD',
+		'**': 'POW',
+		'<<': 'LSHIFT',
+		'>>': 'RSHIFT',
+		'&': 'AND',
+		'|': 'OR',
+		'^': 'XOR',
+		'and': 'AND',
+		'or': 'OR',
+	}
+
+	_self_argdef = ASTArgdefNode(Class, ASTIdentifierNode('<self>', lineno=None, offset=None), None, None, lineno=None, offset=None)
+
+	def _class_init(self, *args, **kwargs):
+		getattr(self, '<init>')()
+		getattr(self, f"<constructor ({', '.join(type(i).__name__ for i in (*args, *kwargs.values()))})>")(*args, **kwargs)
+	_class_init = _class_init.__code__.replace(co_name='<new>')
+
+	@init_defaults
+	def __init__(self, *, name, ns, filename, argdefs=(), lastnodens: lambda: [None, None], firstlineno=0):
+		self.name, self.ns, self.filename, self.lastnodens, self.firstlineno = name, ns, filename, lastnodens, firstlineno
+		self.instrs = list()
+		self.consts = list()
+		self.argnames = list()
+		for i in argdefs:
+			if (i.modifier is not None): raise NotImplementedError("argument modifiers are not supported yet")
+			self.argnames.append(i.name.identifier)
+		self.cellvars = self.argnames.copy()
+		self.srclnotab = list()
+		self.lastln = self.firstlineno
+		self._class_init = self._class_init.replace(co_filename=self.filename, co_consts=tuple(i.replace(co_filename=self.filename) if (isinstance(i, CodeType)) else i for i in self._class_init.co_consts))
+
+	def compile(self):
+		return pyssembly.Code('\n'.join(self.instrs), name=self.name, filename=self.filename.strip('"'), srclnotab=self.srclnotab, firstlineno=self.firstlineno, consts=self.consts, argnames=self.argnames)
+
+	@dispatch
+	def add(self, x: ASTRootNode):
+		self.add(x.code)
+
+	@dispatch
+	def add(self, x: ASTCodeNode):
+		for ii, i in enumerate(x.nodes):
+			assert (i.lineno >= self.lastln)
+			if (i.lineno != self.lastln): self.instrs.append(f"#line {i.lineno}")
+			self.lastln = i.lineno
+			self.lastnodens[0] = i
+			self.add(i)
+
+	@dispatch
+	def add(self, x: ASTValueNode):
+		self.add(x.value)
+
+	@dispatch
+	def add(self, x: ASTVardefNode):
+		typesig = Signature.build(x.type, self.ns)
+		if (x.value is not None):
+			self.load(x.value)
+			self.store(x.name)
+		elif (isinstance(typesig, Class)):
+			self.instrs += [
+				"LOAD		(object)",
+				"GETATTR	(__new__)",
+			]
+			self.load(x.type.type)
+			self.instrs += [
+				"CALL		1",
+				"DUP",
+				"GETATTR	<<init>>",
+				"CALL",
+				"POP",
+			]
+			self.store(x.name)
+
+	@dispatch
+	def add(self, x: ASTAssignmentNode):
+		if (x.inplace_operator is not None): self.instrs.append(f"LOAD	({x.name})")
+		self.load(x.value)
+		if (x.inplace_operator is not None): self.instrs.append(f"IP{self.binopmap[x.inplace_operator.operator]}")
+		if (x.isattr):
+			self.instrs += [
+				"LOAD		$<self>",
+				f"SETATTR	({x.name})",
+			]
+		else: self.store(x.name)
+
+	@dispatch
+	def add(self, x: ASTUnpackAssignmentNode):
+		assert (x.inplace_operator is None) # TODO
+		self.load(x.value)
+		self.instrs.append(f"UNPACK	{len(x.names)}")
+		for name in x.names:
+			self.store(name)
+
+	@dispatch
+	def add(self, x: ASTAttrsetNode):
+		assert (x.assignment.isattr)
+		if (x.assignment.inplace_operator is not None):
+			self.load(x.value)
+			self.instrs += [
+				"DUP",
+				"GETATTR	({x.assignment.name})",
+			]
+			self.load(x.assignment.value)
+			self.instrs += [
+				f"IP{self.binopmap[x.assignment.inplace_operator.operator]}",
+				"ROT",
+			]
+		else:
+			self.load(x.assignment.value)
+			self.load(x.value)
+		self.instrs.append(f"SETATTR	({x.assignment.name})")
+
+	@dispatch
+	def add(self, x: ASTFunccallNode):
+		self.load(x)
+		self.instrs.append("POP")
+
+	@dispatch
+	def add(self, x: ASTBlockNode):
+		self.add(x.code)
+
+	@dispatch
+	def add(self, x: ASTFuncdefNode):
+		code_ns = self.ns.derive(x.name.identifier)
+		name = f"{x.name.identifier}({CallArguments(args=tuple(Signature.build(i, code_ns) for i in x.argdefs))})"
+		self.lastnodens[1] = code_ns
+		fname = f"{self.name}.<{x.__fsig__()}>"
+		f_instrs = Instrs(name=fname, ns=code_ns, filename=self.filename, argdefs=x.argdefs, lastnodens=self.lastnodens, firstlineno=x.lineno)
+		f_instrs.add(x.code)
+		#dlog(f"{fname} instrs:\n"+'\n'.join(f_instrs.instrs)+'\n')
+		self.consts.append(f_instrs.compile().to_code())
+		self.lastnodens[1] = self.ns
+		self.instrs += [
+			f"LOAD		{len(self.consts)-1}",
+			f"LOAD		('{fname}')",
+			"MKFUNC		0", # TODO: flags
+		]
+		self.store(name)
+
+	@dispatch
+	def add(self, x: ASTClassdefNode):
+		code_ns = self.ns.derive(x.name.identifier)
+		name = x.name.identifier
+		self.lastnodens[1] = code_ns
+		cname = str(name)
+		c_instrs = Instrs(name=cname, ns=code_ns, filename=self.filename, lastnodens=self.lastnodens, firstlineno=x.lineno)
+		c_instrs.consts.append(self._class_init)
+		c_instrs.instrs += [
+			f"LOAD		{len(self.consts)-1}",
+			f"LOAD		('<new>')",
+			"MKFUNC		0", # TODO: flags
+		]
+		c_instrs.store('__init__')
+		c_instrs.add(x.code)
+		self.consts.append(c_instrs.compile().to_code())
+		self.lastnodens[1] = self.ns
+		self.instrs += [
+			"LOAD_BUILD_CLASS",
+			f"LOAD		{len(self.consts)-1}",
+			f"LOAD		('{cname}')",
+			"MKFUNC		0", # TODO: flags?
+			f"LOAD		('{cname}')",
+			"CALL		2",
+		]
+		self.store(name)
+
+	@dispatch
+	def add(self, x: ASTKeywordExprNode):
+		if (x.keyword.keyword == 'import'):
+			m = re.fullmatch(r'(?:(?:(\w+):)?(?:([\w./]+)/)?([\w.]+):)?([\w*]+)', x.value.identifier)
+			assert (m is not None)
+			namespace, path, pkg, name = m.groups()
+			if (namespace is None): namespace = 'sl'
+			if (path is None): path = '.'
+			if (pkg is None): pkg = name
+			if (namespace == 'py'):
+				assert (path == '.')
+				self.instrs += [
+					"LOAD		(0)", # TODO
+					"LOAD		(())", # TODO
+					f"IMPORT	({pkg})",
+				]
+				if (name == '*'): self.instrs.append("IMPALL")
+				else:
+					if (name != pkg): self.instrs.append("IMPFROM")
+					self.store(name)
+			elif (namespace == 'sl'):
+				pkg = pkg.replace('.', '/')
+				filename = f"{os.path.join(path, pkg)}.sl"
+				src = open(filename, 'r').read()
+				tl = parse_string(src)
+				ast = build_ast(tl, filename)
+				optimize_ast(ast, validate_ast(ast))
+				instrs = Instrs(name='<module>', ns=validate_ast(ast), filename=filename)
+				instrs.add(ast)
+				code = instrs.compile().to_code()
+				# TODO
+			else: raise WTFException(namespace)
+		elif (x.keyword.keyword == 'return'):
+			self.load(x.value)
+			self.instrs.append("RET")
+		elif (x.keyword.keyword == 'delete'):
+			self.delete(x.value)
+		elif (x.keyword.keyword == 'break'):
+			self.instrs.append("JF :end")
+		else: raise NotImplementedError(x.keyword)
+
+	@dispatch
+	def add(self, x: ASTKeywordDefNode):
+		name = x.name.identifier
+		if (x.keyword.keyword == 'main'):
+			code_ns = self.ns.derive(name)
+			self.lastnodens[1] = code_ns
+			f_instrs = Instrs(name=name, ns=code_ns, filename=self.filename, lastnodens=self.lastnodens, firstlineno=x.lineno)
+			f_instrs.add(x.code)
+			#dlog(f"{name} instrs:\n"+'\n'.join(f_instrs.instrs)+'\n')
+			self.consts.append(f_instrs.compile().to_code())
+			self.lastnodens[1] = self.ns
+			self.instrs += [
+				"LOAD		(__name__)",
+				"LOAD		('__main__')",
+				"CMP		(==)",
+				"JFP		:nomain",
+				f"LOAD		{len(self.consts)-1}",
+				f"LOAD		('{name}')",
+				"MKFUNC		0",
+				"CALL		0",
+				"POP",
+				":nomain",
+			]
+		elif (x.keyword.keyword == 'init'):
+			code_ns = self.ns.derive(name)
+			self.lastnodens[1] = code_ns
+			f_instrs = Instrs(name=name, argdefs=(self._self_argdef,), ns=code_ns, filename=self.filename, lastnodens=self.lastnodens, firstlineno=x.lineno)
+			f_instrs.add(x.code)
+			#dlog(f"{name} instrs:\n"+'\n'.join(f_instrs.instrs)+'\n')
+			self.consts.append(f_instrs.compile().to_code())
+			self.lastnodens[1] = self.ns
+			self.instrs += [
+				f"LOAD		{len(self.consts)-1}",
+				f"LOAD		('{name}')",
+				"MKFUNC		0",
+			]
+			self.store(name)
+		elif (x.keyword.keyword == 'constr'):
+			code_ns = self.ns.derive(name)
+			self.ns.define(x, redefine=True)
+			self.lastnodens[1] = code_ns
+			name = f"<constructor ({S(', ').join(i.type for i in x.argdefs)})>"
+			f_instrs = Instrs(name=name, ns=code_ns, filename=self.filename, argdefs=(self._self_argdef, *x.argdefs), lastnodens=self.lastnodens, firstlineno=x.lineno)
+			f_instrs.add(x.code)
+			#dlog(f"{name} instrs:\n"+'\n'.join(f_instrs.instrs)+'\n')
+			self.consts.append(f_instrs.compile().to_code())
+			self.lastnodens[1] = self.ns
+			self.instrs += [
+				f"LOAD		{len(self.consts)-1}",
+				f"LOAD		('{name}')",
+				"MKFUNC		0", # TODO: flags
+			]
+			self.store(name)
+		else: raise NotImplementedError(x.keyword)
+
+	@dispatch
+	def add(self, x: ASTConditionalNode):
+		self.load(x.condition)
+		self.instrs.append("JFP	:else")
+		self.add(x.code)
+		self.instrs += [
+			"JF	:end",
+			":else",
+			":end",
+		]
+
+	@dispatch
+	def add(self, x: ASTForLoopNode):
+		self.load(x.iterable)
+		#self.cellvars.append(x.name.identifier) # TODO FIXME
+		self.instrs += [
+			"ITER",
+			":for",
+			"FOR	:else",
+		]
+		self.store(x.name)
+		self.add(x.code) # TODO: stack effect (py38)
+		self.instrs += [
+			"JA	:for",
+			":else",
+			":end",
+		]
+
+	@dispatch
+	def add(self, x: ASTWhileLoopNode):
+		self.instrs += [
+			":while",
+		]
+		self.load(x.condition)
+		self.instrs.append("JFP	:else")
+		self.add(x.code) # TODO: stack effect (py38)
+		self.instrs += [
+			"JA	:while",
+			":else",
+			":end",
+		]
+
+	@dispatch
+	def add(self, x: ASTElseClauseNode):
+		ii = -1 - self.instrs[-1].startswith('#line')
+		assert (self.instrs.pop(ii) == ":end")
+		self.add(x.code) # TODO: stack effect (py38)
+		self.instrs.append(":end")
+
+	@dispatch
+	def load(self, x: ASTLiteralNode):
+		self.instrs.append(f"LOAD	({x.literal})")
+
+	@dispatch
+	def load(self, x: ASTIdentifierNode):
+		self.load(x.identifier)
+
+	@dispatch
+	def load(self, x: ASTListNode):
+		for i in x.values:
+			self.load(i)
+		self.instrs.append(f"BUILD_LIST	{len(x.values)}")
+
+	@dispatch
+	def load(self, x: ASTTupleNode):
+		for i in x.values:
+			self.load(i)
+		self.instrs.append(f"BUILD_TUPLE	{len(x.values)}")
+
+	@dispatch
+	def load(self, x: ASTValueNode):
+		self.load(x.value)
+
+	@dispatch
+	def load(self, x: ASTFunccallNode):
+		if (isinstance(x.callable, ASTValueNode) and isinstance(x.callable.value, ASTIdentifierNode) and x.callable.value.identifier in self.ns.signatures and not isinstance(self.ns.signatures[x.callable.value.identifier], Class)):
+			self.load(f"{x.callable.value.identifier}({CallArguments.build(x, self.ns)})")
+		else: self.load(x.callable)
+		n = int()
+
+		for i in x.callargs.callargs:
+			self.load(i)
+			n += 1
+		if (x.callargs.starargs):
+			if (n):
+				self.instrs.append(f"BUILD_TUPLE	{n}")
+				n = 1
+			for i in x.callargs.starargs:
+				self.load(i)
+				n += 1
+			self.instrs.append(f"BUILD_TUPLE_UNPACK_WITH_CALL	{n}")
+			n = 0
+
+		for i in x.callkwargs.callkwargs:
+			self.load(f"'{i[0]}'")
+			self.load(i[1])
+			n += 1
+		if (n and (x.callargs.starargs or x.callkwargs.starkwargs)):
+			self.instrs.append(f"BUILD_MAP	{n}")
+			n = 1
+		if (x.callkwargs.starkwargs):
+			for i in x.callkwargs.starkwargs:
+				self.load(i)
+				n += 1
+			self.instrs.append(f"BUILD_MAP_UNPACK_WITH_CALL	{n}")
+			n = 1
+
+		self.instrs.append(f"CALL{'EX' if (x.callargs.starargs or x.callkwargs.starkwargs) else 'KW' if (x.callkwargs.callkwargs) else ''}	{n}")
+
+	@dispatch
+	def load(self, x: ASTAttrgetNode):
+		self.load(x.value)
+		assert (x.optype.special == '.') # TODO
+		self.instrs.append(f"GETATTR	({x.attr})")
+
+	@dispatch
+	def load(self, x: ASTUnaryExprNode):
+		self.load(x.value)
+		self.instrs.append(self.unopmap[x.operator.operator])
+
+	@dispatch
+	def load(self, x: ASTBinaryExprNode):
+		self.load(x.lvalue)
+		char = isinstance(Signature.build(x.lvalue, self.ns), stdlib.char)
+		if (char): self.instrs.append("CALL	(ord)	1")
+		if (x.operator.operator == 'xor'): self.instrs.append("BOOL")
+		self.load(x.rvalue)
+		if (char and isinstance(Signature.build(x.rvalue, self.ns), stdlib.char)): self.instrs.append("CALL	(ord)	1")
+		if (x.operator.operator == 'xor'): self.instrs.append("BOOL")
+		if (x.operator.operator == 'to'): self.instrs.append("CALL	(range)	2")
+		else: self.instrs.append(f"CMP	({x.operator.operator})" if (x.operator.operator in dis.cmp_op) else self.binopmap[x.operator.operator])
+		if (x.operator.operator == 'xor'): self.instrs.append("BOOL")
+		if (char and x.operator.operator not in logical_operators): self.instrs.append("CALL	(chr)	1")
+
+	@dispatch
+	def load(self, x: ASTItemgetNode):
+		self.load(x.value)
+		self.load(x.key)
+		self.instrs.append("SUBSCR")
+
+	@dispatch
+	def load(self, x: str):
+		self.instrs.append(f"LOAD	{f'${x}' if (x in self.cellvars) else f'<{x}>'}")
+
+	@dispatch
+	def load(self, x):
+		self.instrs.append(f"LOAD_CONST	({repr(x)})")
+
+	@dispatch
+	def store(self, x: ASTIdentifierNode):
+		self.store(x.identifier)
+
+	@dispatch
+	def store(self, x: str):
+		self.instrs.append(f"STORE	{f'${x}' if (x in self.cellvars) else f'<{x}>'}")
+
+	@dispatch
+	def delete(self, x: ASTIdentifierNode):
+		self.delete(x.identifier)
+
+	@dispatch
+	def delete(self, x: str):
+		self.instrs.append(f"DELETE	{f'${x}' if (x in self.cellvars) else f'<{x}>'}")
+
+class PyssemblyCompiler(Compiler):
+	ext = '.pyc'
+
+	@classmethod
+	def compile_ast(cls, ast, ns, *, filename):
+		instrs = Instrs(name='<module>', ns=ns, filename=filename)
+
+		instrs.consts.append(compile(open(std.__file__).read(), '<std>', 'exec'))
+		instrs.instrs += [
+			f"LOAD	{len(instrs.consts)-1}",
+			"LOAD	('<std>')",
+			"MKFUNC	0", # TODO?
+			"CALL",
+		]
+
+		try: instrs.add(ast)
+		except Exception as ex: raise SlCompilationError('Compilation error', instrs.lastnodens[0], scope=instrs.lastnodens[1].scope) from ex
+
+		#dlog("Instrs:\n"+'\n'.join(instrs.instrs)+'\n')
+
+		try:
+			code = instrs.compile().to_code()
+			#dis.show_code(code); dis.dis(code); print()
+			code = pyssembly.asm(code)
+		except pyssembly.PyssemblyError as ex:
+			print('Error:', ex)
+			try: code = ex.code.to_code()
+			except pyssembly.PyssemblyError: pass
+			else:
+				print("\nHere is full pyssembly code 'til the errorneous line:\n")
+				dis.dis(code)
+			raise SlCompilationError('Pyssembly error', ast, scope=instrs.ns) from ex
+
+		return code
+
+# by Sdore, 2020
--- a/compilers/pyssembly/std.py
+++ b/compilers/pyssembly/std.py
@@ -0,0 +1,2 @@
+class stdio:
+	println = print
--- a/compilers/pyssembly/typeshed
+++ b/compilers/pyssembly/typeshed
--- a/compilers/sbc.py
+++ b/compilers/sbc.py
@@ -6,7 +6,11 @@ from Slang.ast import *
 from utils import *

 NOP	= 0x00
-RET	= 0x01
+END	= 0x01
+POP	= 0x02
+RET	= 0x03
+BLTIN	= 0x04
+CODE	= 0x05

 POS	= 0x10
 NEG	= 0x11
@@ -24,15 +28,28 @@ ADD	= 0x20
 SUB	= 0x21
 MUL	= 0x22
 DIV	= 0x23
-FLRDIV	= 0x24
+IDIV	= 0x24
 MOD	= 0x25
 POW	= 0x26
-SHL	= 0x27
-SHR	= 0x28
+LSH	= 0x27
+RSH	= 0x28
 AND	= 0x29
 OR	= 0x2a
 XOR	= 0x2b

+EQ	= 0x30
+NE	= 0x31
+LT	= 0x32
+GT	= 0x33
+LE	= 0x34
+GE	= 0x35
+IS	= 0x36
+ISNOT	= 0x37
+
+IF	= 0x40
+ELSE	= 0x41
+EXEC	= 0x42
+
 ALLOC	= 0xa0
 EXTEND	= 0xa1
 CONST	= 0xa2
@@ -40,26 +57,81 @@ JUMPF	= 0xa3
 JUMPB	= 0xa4
 SCPGET	= 0xa5
 SCPSET	= 0xa6
+CALL	= 0xa7

 HASARG	= 0xa0

+def readVarInt(s):
+	r = int()
+	i = int()
+	while (True):
+		b = s.recv(1)[0]
+		r |= (b & (1 << 7)-1) << (7*i)
+		if (not b & (1 << 7)): break
+		i += 1
+	return r
+
+def writeVarInt(v):
+	assert v >= 0
+	r = bytearray()
+	while (True):
+		c = v & (1 << 7)-1
+		v >>= 7
+		if (v): c |= (1 << 7)
+		r.append(c)
+		if (not v): break
+	return bytes(r)
+
 class Instrs:
 	unops = '+-!~'
 	binops = (*'+-*/%', '**', '<<', '>>', '&', '|', '^')
+	unopmap = {
+		'+': POS,
+		'-': NEG,
+		'!': NOT,
+		'~': INV,
+		'not': NOT,
+	}
+	binopmap = {
+		'+': ADD,
+		'-': SUB,
+		'*': MUL,
+		'/': DIV,
+		'//': IDIV,
+		'%': MOD,
+		'**': POW,
+		'<<': LSH,
+		'>>': RSH,
+		'&': AND,
+		'|': OR,
+		'^': XOR,
+
+		'==': EQ,
+		'!=': NE,
+		'<': LT,
+		'>': GT,
+		'<=': LE,
+		'>=': GE,
+		'is': IS,
+		'is not': ISNOT,
+	}

 	@init_defaults
-	def __init__(self, *, name, ns, filename, argdefs=()):
-		self.ns = ns
+	def __init__(self, *, name, ns, filename, scpcells: indexset):
+		self.name, self.ns, self.filename, self.scpcells = name, ns, filename, scpcells
 		self.instrs = bytearray()

 	def compile(self):
-		raise TODO
+		return bytes(self.instrs)

 	@dispatch
-	def add(self, opcode: int, oparg: int = None):
+	def add(self, opcode: lambda x: isinstance(x, int) and x < HASARG):
 		self.instrs.append(opcode)
-		if (opcode >= HASARG): self.instrs.append(oparg)
-		else: assert oparg is None
+
+	@dispatch
+	def add(self, opcode: lambda x: isinstance(x, int) and x >= HASARG, oparg: int):
+		self.instrs.append(opcode)
+		self.instrs.append(oparg)

 	@dispatch
 	def add(self, x: ASTRootNode):
@@ -67,7 +139,6 @@ class Instrs:

 	@dispatch
 	def add(self, x: ASTCodeNode):
-		lastln = int()
 		for i in x.nodes:
 			self.add(i)

@@ -83,15 +154,14 @@ class Instrs:

 	@dispatch
 	def add(self, x: ASTAssignmentNode):
-		if (x.inplace_operator is not None): self.instrs.append(f"LOAD	({x.name})")
+		if (x.inplace_operator is not None): raise NotImplementedError()
 		self.load(x.value)
-		if (x.inplace_operator is not None): self.instrs.append(f"INP_{self.binopmap[x.inplace_operator.operator]}")
 		self.store(x.name)

 	@dispatch
 	def add(self, x: ASTFunccallNode):
 		self.load(x)
-		self.instrs.append("POP")
+		self.add(POP)

 	@dispatch
 	def add(self, x: ASTBlockNode):
@@ -101,46 +171,52 @@ class Instrs:
 	def add(self, x: ASTFuncdefNode):
 		code_ns = self.ns.derive(x.name.identifier)
 		name = f"{x.name.identifier}__{self.ns.signatures[x.name.identifier].call.index(CallArguments(args=tuple(Signature.build(i, code_ns) for i in x.argdefs)))}"
-		f_instrs = Instrs(name=f"{self.name}.{name}", ns=code_ns, filename=self.filename, argdefs=x.argdefs)
+		fname = f"{self.name}.<{x.__fsig__()}>"
+		self.scpcells[name]
+		f_instrs = Instrs(name=fname, ns=code_ns, filename=self.filename, scpcells=self.scpcells.copy())
+		for i in x.argdefs:
+			f_instrs.scpcells[i.name.identifier]
 		f_instrs.add(x.code)
-		#dlog(f"{x.__fsig__()} instrs:\n"+'\n'.join(f_instrs.instrs)+'\n')
-		self.consts.append(f_instrs.compile().to_code())
-		self.instrs += [
-			f"LOAD	{len(self.consts)-1}",
-			f"LOAD	('{self.name}.{name}')",
-			f"MAKE_FUNCTION	0", # TODO: flags
-		]
+		self.add(CODE)
+		self.instrs += f_instrs.instrs
+		self.add(END)
+		self.store(name+'.len')
 		self.store(name)

 	@dispatch
 	def add(self, x: ASTKeywordExprNode):
 		if (x.keyword.keyword == 'import'):
 			ns, _, name = x.value.identifier.partition('::')
-			assert ns == 'py'
-			self.instrs += [
-				"LOAD	(0)", # TODO
-				"LOAD	(None)", # TODO
-			]
-			self.instrs.append(f"IMPORT_NAME	({name})")
+			raise TODO
 			self.store(name)
 		elif (x.keyword.keyword == 'return'):
 			self.load(x.value)
-			self.instrs.append("RET")
+			self.add(RET)
+		else: raise NotImplementedError(x.keyword)
+
+	@dispatch
+	def add(self, x: ASTKeywordDefNode):
+		if (x.keyword.keyword == 'main'):
+			name = '<main>'
+			code_ns = self.ns.derive(name)
+			f_instrs = Instrs(name=name, ns=code_ns, filename=self.filename)
+			f_instrs.add(x.code)
+			self.add(CODE)
+			self.instrs += f_instrs.instrs
+			self.add(END)
+			self.add(EXEC)
+			self.add(POP)
 		else: raise NotImplementedError(x.keyword)

 	@dispatch
 	def add(self, x: ASTConditionalNode):
 		self.load(x.condition)
-		self.instrs.append("JPOPF	:else")
+		self.add(IF)
 		self.add(x.code)
-		self.instrs += [
-			"JUMPF	:end",
-			":else",
-			":end",
-		]
+		self.add(END)

-	@dispatch
-	def add(self, x: ASTForLoopNode):
+	#@dispatch
+	def add_(self, x: ASTForLoopNode):
 		self.load(x.iterable)
 		#self.cellvars.append(x.name.identifier) # TODO FIXME
 		self.instrs += [
@@ -158,8 +234,8 @@ class Instrs:
 			":end",
 		]

-	@dispatch
-	def add(self, x: ASTWhileLoopNode):
+	#@dispatch
+	def add_(self, x: ASTWhileLoopNode):
 		self.instrs += [
 			"SETUP_LOOP	:end",
 			":while",
@@ -174,8 +250,8 @@ class Instrs:
 			":end",
 		]

-	@dispatch
-	def add(self, x: ASTElseClauseNode):
+	#@dispatch
+	def add_(self, x: ASTElseClauseNode):
 		assert (self.instrs[-1] == ":end")
 		popped = [self.instrs.pop()]
 		if (self.instrs[-1] == "POP_BLOCK"): popped.append(self.instrs.pop())
@@ -184,7 +260,16 @@ class Instrs:

 	@dispatch
 	def load(self, x: ASTLiteralNode):
-		self.instrs.append(f"LOAD	({x.literal})")
+		sig = Signature.build(x, ns=self.ns)
+		if (hasattr(sig, 'fmt')):
+			v = struct.pack(sig.fmt, int(x.literal))
+		elif (isinstance(sig, stdlib.int)):
+			v = writeVarInt(int(x.literal))
+		elif (isinstance(sig, stdlib.str)):
+			v = x.literal.encode('utf8')
+		else: raise NotImplementedError(sig)
+		self.add(CONST, len(v))
+		self.instrs += v

 	@dispatch
 	def load(self, x: ASTIdentifierNode):
@@ -196,42 +281,29 @@ class Instrs:

 	@dispatch
 	def load(self, x: ASTFunccallNode):
-		if (isinstance(x.callable, ASTValueNode) and isinstance(x.callable.value, ASTIdentifierNode) and x.callable.value.identifier in self.ns.signatures):
-			self.load(f"{x.callable.value.identifier}__{self.ns.signatures[x.callable.value.identifier].call.index(CallArguments.build(x, self.ns))}")
-		else: self.load(x.callable)
-		n = int()
+		nargs = int()

 		for i in x.callargs.callargs:
 			self.load(i)
-			n += 1
-		if (x.callargs.starargs):
-			if (n):
-				self.instrs.append(f"BUILD_TUPLE	{n}")
-				n = 1
-			for i in x.callargs.starargs:
-				self.load(i)
-				n += 1
-			self.instrs.append(f"BUILD_TUPLE_UNPACK_WITH_CALL	{n}")
-			n = 0
+			nargs += 1
+		if (x.callargs.starargs): raise NotImplementedError()

-		for i in x.callkwargs.callkwargs:
-			self.load(f"'{i[0]}'")
-			self.load(i[1])
-			n += 1
-		if (n and (x.callargs.starargs or x.callkwargs.starkwargs)):
-			self.instrs.append(f"BUILD_MAP	{n}")
-			n = 1
-		if (x.callkwargs.starkwargs):
-			for i in x.callkwargs.starkwargs:
-				self.load(i)
-				n += 1
-			self.instrs.append(f"BUILD_MAP_UNPACK_WITH_CALL	{n}")
-			n = 1
+		if (x.callkwargs.callkwargs): raise NotImplementedError()
+		if (x.callkwargs.starkwargs): raise NotImplementedError()

-		self.instrs.append(f"CALL{'EX' if (x.callargs.starargs or x.callkwargs.starkwargs) else 'KW' if (x.callkwargs.callkwargs) else ''}	{n}")
+		if (isinstance(x.callable, ASTValueNode) and isinstance(x.callable.value, ASTIdentifierNode) and x.callable.value.identifier in self.ns.signatures):
+			name = f"{x.callable.value.identifier}__{self.ns.signatures[x.callable.value.identifier].call.index(CallArguments.build(x, self.ns))}"
+			self.load(name)
+			self.load(name+'.len')
+			self.add(EXEC)
+		else:  # builtin
+			#self.add(ITOA) # TODO FIXME cast
+			self.add(BLTIN)
+			self.instrs += x.callable.value.identifier.encode('ascii')+b'\0'
+			self.add(CALL, nargs)

-	@dispatch
-	def load(self, x: ASTAttrgetNode):
+	#@dispatch
+	def load_(self, x: ASTAttrgetNode):
 		self.load(x.value)
 		assert x.optype.special == '.' # TODO
 		self.instrs.append(f"GETATTR	({x.attr})")
@@ -239,31 +311,24 @@ class Instrs:
 	@dispatch
 	def load(self, x: ASTUnaryExprNode):
 		self.load(x.value)
-		self.instrs.append(self.unopmap[x.operator.operator])
+		self.add(self.unopmap[x.operator.operator])

 	@dispatch
 	def load(self, x: ASTBinaryExprNode):
 		self.load(x.lvalue)
-		char = isinstance(Signature.build(x.lvalue, self.ns), stdlib.char)
-		if (char): self.instrs.append("CALL	(ord) 1")
-		if (x.operator.operator == 'xor'): self.instrs.append("BOOL")
 		self.load(x.rvalue)
-		if (char and isinstance(Signature.build(x.rvalue, self.ns), stdlib.char)): self.instrs.append("CALL	(ord) 1")
-		if (x.operator.operator == 'xor'): self.instrs.append("BOOL")
-		if (x.operator.operator == 'to'): self.instrs.append("CALL	(range) 2")
-		else: self.instrs.append(self.binopmap[x.operator.operator])
-		if (x.operator.operator == 'xor'): self.instrs.append("BOOL")
-		if (char and x.operator.operator not in keyword_operators): self.instrs.append("CALL	(chr) 1")
+		if (x.operator.operator == 'to'): raise NotImplementedError()
+		else: self.add(self.binopmap[x.operator.operator])

-	@dispatch
-	def load(self, x: ASTItemgetNode):
+	#@dispatch
+	def load_(self, x: ASTItemgetNode):
 		self.load(x.value)
 		self.load(x.key)
 		self.instrs.append("SUBSCR")

 	@dispatch
 	def load(self, x: str):
-		self.instrs.append(f"LOAD	{f'${x}' if (x in self.cellvars) else f'({x})'}")
+		self.add(SCPGET, self.scpcells[x])

 	@dispatch
 	def store(self, x: ASTIdentifierNode):
@@ -271,18 +336,16 @@ class Instrs:

 	@dispatch
 	def store(self, x: str):
-		self.instrs.append(f"STORE	{f'${x}' if (x in self.cellvars) else f'({x})'}")
+		self.add(SCPSET, self.scpcells[x])
+
+class SBCCompiler(Compiler):
+	ext = '.sbc'

-class PyssemblyCompiler(Compiler):
 	@classmethod
 	def compile_ast(cls, ast, ns, *, filename):
 		instrs = Instrs(name='<module>', ns=ns, filename=filename)
 		instrs.add(ast)
-		#dlog("Instrs:\n"+'\n'.join(instrs.instrs)+'\n')
-		code = instrs.compile().to_code()
-		#dis.show_code(code)
-		#dis.dis(code)
-		#print()
+		code = instrs.compile()
 		return code

 # by Sdore, 2019
--- a/lexer.py
+++ b/lexer.py
@@ -13,21 +13,30 @@ def read_token(src, *, lineno, offset, lineoff):
 		if (isinstance(r, int) and r <= 0): length = max(length, -r); continue
 		n, s = r if (isinstance(r, tuple)) else (r, src[:r])
 		return (offset+n, Token(ii, s, lineno=lineno, offset=offset+lineoff))
-	else: raise SlSyntaxError("Invalid token", line, lineno=lineno, offset=offset+lineoff, length=length)
+	else: raise SlSyntaxError("Invalid token", line, lineno=lineno, offset=offset+lineoff, length=length+l)

 def parse_expr(src, *, lineno=1, lineoff=0):
 	r = list()
+	lines = src.count('\n')
 	offset = int()
+	continueln = False
 	while (True):
-		offset, tok = read_token(src, lineno=lineno, offset=offset, lineoff=lineoff)
-		if (tok is None): break
+		offset, tok = read_token(src, lineno=lines-src[offset:].count('\n')+lineno, offset=offset, lineoff=lineoff)
+		if (tok is None):
+			if (not continueln): break
+			continueln = False
+			offset += 1
+			lineoff = -offset
+			continue
+		elif (continueln and tok.token[0] != '#'): raise SlSyntaxError("Expected newline or comment after line continuation", src, lineno=lines-src[offset:].count('\n')+lineno, offset=tok.offset, length=tok.length)
 		r.append(tok)
+		if (tok.token[0] != '#'): continueln = (tok.token == '\\' and tok.offset)
 	return offset, r

-def parse_string(src):
+def parse_string(src, lnooff=0):
 	src = src.rstrip()
 	tl = list()
-	lines = src.count('\n')
+	lines = src.count('\n')+lnooff
 	lineoff = int()
 	while (src):
 		offset, r = parse_expr(src, lineno=lines-src.count('\n')+1, lineoff=lineoff)
@@ -39,4 +48,4 @@ def parse_string(src):
 		tl.append(r)
 	return tl

-# by Sdore, 2019
+# by Sdore, 2020
--- a/repl.py
+++ b/repl.py
@@ -4,13 +4,15 @@
 import readline
 from .ast import *
 from .lexer import *
-from utils import *
+from utils.nolog import *

@dispatch
 def execute_node(node: ASTCodeNode, ns):
+	r = None
 	for i in node.nodes:
+		if (isinstance(i, ASTElseClauseNode) and r is not None): continue
 		r = execute_node(i, ns)
-		if (r is not None):
+		if (r not in (None, ...)):
 			ns.values['_'] = r
 			print(repr(r))
 	else: return
@@ -20,13 +22,17 @@ def execute_node(node: ASTCodeNode, ns):
 def execute_node(node: ASTVardefNode, ns):
 	ns.values[node.name] = node.value

+@dispatch
+def execute_node(node: ASTBlockNode, ns):
+	return execute_node(node.code, ns)
+
@dispatch
 def execute_node(node: ASTFuncdefNode, ns):
 	ns.values[node.name.identifier] = (node.argdefs, node.code)

@dispatch
 def execute_node(node: ASTAssignmentNode, ns):
-	ns.values[node.name] = node.value
+	ns.values[node.name] = execute_node(ASTBinaryExprNode(node.name, node.inplace_operator, node.value, lineno=node.lineno, offset=node.offset), ns) if (node.inplace_operator is not None) else node.value

@dispatch
 def execute_node(node: ASTFunccallNode, ns):
@@ -42,48 +48,161 @@ def execute_node(node: ASTValueNode, ns):

@dispatch
 def execute_node(node: ASTIdentifierNode, ns):
-	return ns.values[node]
+	try: return ns.values[node]
+	except KeyError: raise SlValidationError(f"{node} is not initialized", node, scope=ns.scope)

@dispatch
 def execute_node(node: ASTLiteralNode, ns):
-	return eval(str(node.literal))
+	return eval(node.literal) if (isinstance(node.literal, str)) else node.literal
+
+@dispatch
+def execute_node(node: ASTListNode, ns):
+	return node.values

@dispatch
 def execute_node(node: ASTKeywordExprNode, ns):
-	if (node.keyword.keyword == 'return'): return execute_node(node.value, ns)
-	raise NotImplementedError(node.keyword)
+	#if (node.keyword.keyword == 'return'): return execute_node(node.value, ns) # TODO FIXME???
+	#el
+	if (node.keyword.keyword == 'delete'): ns.delete(node.value)
+	else: raise NotImplementedError(node.keyword)
+
+@dispatch
+def execute_node(node: ASTConditionalNode, ns):
+	if (execute_node(node.condition, ns)):
+		execute_node(node.code, ns)
+	else: return
+	return ...
+
+@dispatch
+def execute_node(node: ASTForLoopNode, ns):
+	for i in execute_node(node.iterable, ns):
+		execute_node(node.code, ns)
+	else: return
+	return ...

@dispatch
 def execute_node(node: ASTUnaryExprNode, ns):
-	return eval(f"{node.operator.operator} {execute_node(node.value, ns)}")
+	value = execute_node(node.value, ns)
+	return eval(f"{node.operator.operator} value")

@dispatch
 def execute_node(node: ASTBinaryExprNode, ns):
-	return eval(f"{execute_node(node.lvalue, ns)} {node.operator.operator} {execute_node(node.rvalue, ns)}")
+	lvalue = execute_node(node.lvalue, ns)
+	rvalue = execute_node(node.rvalue, ns)
+	if (node.operator.operator == 'xor'): return eval("(lvalue and not rvalue) or (rvalue and not lvalue)")
+	elif (node.operator.operator == 'to'): return range(lvalue, rvalue)
+	else: return eval(f"lvalue {node.operator.operator} rvalue")
+
+class Completer:
+	def __init__(self, namespace):
+		self.namespace = namespace
+
+	def complete(self, text, state):
+		if (state == 0):
+			if ('.' in text): self.matches = self.attr_matches(text)
+			else: self.matches = self.global_matches(text)
+		try: return self.matches[state]
+		except IndexError: return None
+
+	def _callable_postfix(self, val, word):
+		if (isinstance(val, ASTCallableNode)): word += '('
+		return word
+
+	def global_matches(self, text):
+		matches = list()
+		seen = set()
+		n = len(text)
+
+		for word in keywords:
+			if (word[:n] != text): continue
+			seen.add(word)
+			matches.append(word+' ')
+
+		for word, val in self.namespace.values.items():
+			if (word[:n] != text or word in seen): continue
+			seen.add(word)
+			matches.append(self._callable_postfix(val, word))
+
+		return matches
+
+	def attr_matches(self, text):
+		m = re.match(r"(\w+(\.\w+)*)\.(\w*)", text)
+		if (m is None): return ()
+		expr, attr = m.group(1, 3)
+		try: obj = self.namespace.values[expr] # TODO FIXME
+		except KeyError: return ()
+
+		words = set() # TODO FIXME attrs
+
+		matches = list()
+		n = len(attr)
+		if (attr == ''): noprefix = '_'
+		elif (attr == '_'): noprefix = '__'
+		else: noprefix = None
+
+		while (True):
+			for word in words:
+				if (word[:n] != attr or (noprefix and word[:n+1] == noprefix)): continue
+				match = f"{expr}.{word}"
+				try: val = getattr(obj, word)
+				except Exception: pass  # Include even if attribute not set
+				else: match = self._callable_postfix(val, match)
+				matches.append(match)
+			if (matches or not noprefix): break
+			if (noprefix == '_'): noprefix = '__'
+			else: noprefix = None
+
+		matches.sort()
+		return matches

 def repl():
 	ns = Namespace('<repl>')
-	#ns.values['print'] = print
+	ns.define(ASTIdentifierNode('_', lineno=None, offset=None), stdlib.Any())
+
+	completer = Completer(ns)
+	histfile = os.path.expanduser('~/.sli_history')
+	try: readline.read_history_file(histfile)
+	except FileNotFoundError: pass
+	for i in (
+		'set colored-completion-prefix on',
+		'set enable-bracketed-paste on',
+		#'set horizontal-scroll-mode on',
+		'set skip-completed-text on',
+		'tab: complete',
+	): readline.parse_and_bind(i)
+	readline.set_completer(completer.complete)
+	#readline.set_completion_display_matches_hook(completer.display) # TODO
+
 	l = list()
 	tl = list()
-	while (True):
-		try:
-			l.append(input(f"\1\033[1;93m\2{'...' if (tl) else '>>>'}\1\033[0m\2 "))
-			tll = parse_string(l[-1])
-			if (not tll): continue
-			tl += tll
-			if (tl[-1][-1].token == '\\'): continue
-			if (len(tl) >= 2 and tl[-2][-1].token == '\\'): tl[-1] = tl[-2][:-1]+tl.pop()
-			if (tl[0][-1].token == '{' and tl[-1][-1].token != '}'): continue
-			ast = build_ast(tl, interactive=True)
-			validate_ast(ast, ns)
-			optimize_ast(ast, ns)
-			execute_node(ast.code, ns)
-		except (EOFError, KeyboardInterrupt): break
-		except (SlSyntaxError, SlValidationError) as ex:
-			ex.line = l[ex.lineno-1]
-			print(ex)
-		tl.clear()
-		l.clear()

-# by Sdore, 2019
+	try:
+		while (True):
+			try:
+				l.append(input(f"\1\033[1;93m\2{'...' if (tl) else '>>>'}\1\033[0m\2 "))
+				tll = parse_string(l[-1], lnooff=len(l)-1)
+				if (not tll): l.pop(); continue
+				tl += tll
+				if (tl[-1][-1].token == '\\'): continue
+				#if (len(tl) >= 2 and tl[-2][-1].token == '\\'): tl[-1] = tl[-2][:-1]+tl.pop() # TODO FIXME?: [['a', '+', '\\'], 'b'] --> [['a', '+', 'b']]
+				if (tl[0][-1].token == '{' and tl[-1][-1].token != '}'): continue
+				ast = build_ast(tl, interactive=True)
+				validate_ast(ast, ns)
+				optimize_ast(ast, ns)
+				execute_node(ast.code, ns)
+			except KeyboardInterrupt:
+				buf = readline.get_line_buffer()
+				print(f"\r\033[2m^C{'> '+buf if (buf) else ' '}\033[0m")
+			except EOFError:
+				print(end='\r\033[K')
+				break
+			except (SlSyntaxError, SlValidationError) as ex:
+				ex.line = l[ex.lineno-1]
+				print(ex)
+			tl.clear()
+			l.clear()
+	finally: readline.write_history_file(histfile)
+
+if (__name__ == '__main__'): repl()
+
+# by Sdore, 2020
--- a/sl/Slang/Slang.sl
+++ b/sl/Slang/Slang.sl
@@ -0,0 +1,17 @@
+# Slang
+
+import lexer:*
+
+str src = "main {print('hello');}"
+
+main {
+	stdio.println("Source: {"+src+"}\n")
+
+	list tl = parse_string(src)
+	stdio.println(tl)
+	stdio.println("Tokens:")
+	stdio.println(tl)
+	stdio.println("\n")
+}
+
+# by Sdore, 2020
--- a/sl/Slang/lexer.sl
+++ b/sl/Slang/lexer.sl
@@ -0,0 +1,74 @@
+# Slang lexer
+
+import tokens:*
+
+tuple read_token(str src, int lineno, int offset, int lineoff) {
+	tuple c = lstripcount(src#|[offset:]|#, whitespace)
+	int l = c[0]
+	src = c[1]
+	str line = src
+	offset += l
+	if not src or src[0] in '\n;' {
+		return (offset, None)
+	}
+	int length = 0
+	int ii = -1
+	for i in Token.types {
+		ii += 1
+		auto r = globals['find_'+i.casefold()](src) or 0
+		if r isof int and r <= 0 {
+			length = max(length, -r)
+			continue
+		}
+		tuple c
+		if r isof tuple {
+			c = r
+		}
+		else {
+			c = (r, src[:r])
+		}
+		int n = c[0]
+		str s = c[1]
+		return (offset+n, Token(ii, s, lineno=lineno, offset=offset+lineoff))
+	} #else raise SlSyntaxError("Invalid token", line, lineno=lineno, offset=offset+lineoff, length=length)
+	return (0, Token())
+}
+
+tuple parse_expr(str src, int lineno = 1, int lineoff = 0) {
+	list r = [Token]
+	int offset
+	while 1 {
+		offset, tok = read_token(src, lineno=lineno, offset=offset, lineoff=lineoff)
+		if tok is None {
+			break
+		}
+		r.append(tok)
+	}
+	return (offset, r)
+}
+
+list parse_string(str src) {
+	src = src.rstrip()
+	list tl = [Token]
+	int lines = src.count('\n')
+	int lineoff = 0
+	while src {
+		tuple c = parse_expr(src, lineno=lines-src.count('\n')+1, lineoff=lineoff)
+		int offset = c[0]
+		list r = c[1]
+		lineoff += offset
+		if offset < src.len {
+			if src[offset] == '\n' {
+				lineoff = 0
+			}
+			else {
+				lineoff += 1
+			}
+		}
+		src = src[offset+1:]
+		tl.append(r)
+	}
+	return tl
+}
+
+# by Sdore, 2020
--- a/sl/Slang/tokens.sl
+++ b/sl/Slang/tokens.sl
@@ -0,0 +1,49 @@
+# Slang tokens
+
+str whitespace = ' \t\r\v\f'
+
+tuple lstripcount(str s, str chars) {
+	int ii = -1
+	char i
+	for i in s {
+		ii += 1
+		if i not in chars {
+			break
+		}
+	}
+	else {
+		ii = 0
+	}
+	return (ii, s#|[ii:]|#)
+}
+
+class Token {
+	int type
+	str token
+	int lineno
+	int offset
+
+	tuple types# = ('SPECIAL', 'OPERATOR', 'LITERAL', 'KEYWORD', 'IDENTIFIER')  # order is also resolution order
+
+	constr(int type, str token, int lineno, int offset) {
+		#.type, .token, .lineno, .offset = type, token, lineno, offset
+	}
+
+	#|repr {
+		return "<Token {.types[.type]} «{repr(.token)[1:-1]}» at line {.lineno}, offset {.offset}>"
+	}|#
+
+	#|eq {
+		#return super() == x or .token == x
+	}|#
+
+	#|property typename {
+		#return .types[.type]
+	}
+
+	property length {
+		#return .token.length
+	}|#
+}
+
+# by Sdore, 2020
--- a/slang.lang
+++ b/slang.lang
@@ -0,0 +1,288 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<language id="slang" name="Slang" version="2.0" _section="Script">
+	<metadata>
+		<property name="mimetypes">text/x-slang;application/x-slang</property>
+		<property name="globs">*.sl</property>
+		<property name="line-comment-start">#</property>
+		<property name="block-comment-start">#|</property>
+		<property name="block-comment-start">|#</property>
+	</metadata>
+
+	<styles>
+		<style id="comment"		name="Comment"			map-to="def:comment"/>
+		<style id="keyword"		name="Keyword"			map-to="def:keyword"/>
+		<style id="reserved"		name="Reserved Keyword"		map-to="def:reserved"/>
+		<style id="string"		name="String"			map-to="def:string"/>
+		<style id="multiline-string"	name="Multi-line String"	map-to="def:string"/>
+		<style id="character"		name="Character"		map-to="def:character"/>
+		<style id="escaped-char"	name="Escaped Character"	map-to="def:special-char"/>
+		<style id="boolean"		name="Boolean"			map-to="def:boolean"/>
+		<style id="floating-point"	name="Floating point number"	map-to="def:floating-point"/>
+		<style id="decimal"		name="Decimal number"		map-to="def:decimal"/>
+		<style id="base-n-integer"	name="Base-N number"		map-to="def:base-n-integer"/>
+		<style id="complex"		name="Complex number"		map-to="def:complex"/>
+		<style id="builtin-constant"	name="Builtin Constant"		map-to="def:special-constant"/>
+		<style id="builtin-object"	name="Builtin Object"		map-to="def:function"/>
+		<style id="builtin-type"	name="Builtin Type"		map-to="def:type"/>
+		<style id="function-name"	name="Function Name"		map-to="def:function"/>
+		<style id="class-name"		name="Class Name"		map-to="def:function"/>
+		<style id="decorator"		name="Decorator"		map-to="def:preprocessor"/>
+	</styles>
+
+	<definitions>
+		<define-regex id="identifier">[_\w][_\w\d]*</define-regex>
+		<define-regex id="number">[1-9][0-9]*</define-regex>
+
+		<define-regex id="identifier-path" extended="true">
+			(\%{identifier}\.)*\%{identifier}
+		</define-regex>
+		<define-regex id="relative-path" extended="true">
+			(\.*\%{identifier-path}|\.+)
+		</define-regex>
+
+		<context id="comment" style-ref="comment" end-at-line-end="true" class-disabled="no-spell-check" class="comment">
+			<start>#</start>
+			<include>
+				<context ref="def:in-line-comment"/>
+			</include>
+		</context>
+		<context id="multiline-comment" style-ref="comment" class-disabled="no-spell-check" class="comment">
+			<start>#\|</start>
+			<end>\|#</end>
+			<include>
+				<context ref="def:in-comment"/>
+			</include>
+		</context>
+		<context id="close-comment-outside-comment" style-ref="error">
+			<match>\|#(?!#\|)</match>
+		</context>
+
+		<context id="escaped-char" style-ref="escaped-char" extend-parent="true">
+			<match extended="true">
+				\\(								 # leading backslash
+				[\\'"abfnrtv]		 | # single escaped char
+				N\{[0-9A-Z\ -]+\} | # named unicode character
+				u[0-9A-Fa-f]{4}	 | # xxxx - character with 16-bit hex value xxxx
+				U[0-9A-Fa-f]{8}	 | # xxxxxxxx - character with 32-bit hex value xxxxxxxx
+				x[0-9A-Fa-f]{1,2} | # \xhh - character with hex value hh
+				[0-7]{1,3}					# \ooo - character with octal value ooo
+				)
+			</match>
+		</context>
+
+		<context id="multiline-double-quoted-string" style-ref="string" class="string" class-disabled="no-spell-check">
+			<start>"""</start>
+			<end>"""</end>
+			<include>
+				<context ref="escaped-char"/>
+			</include>
+		</context>
+
+		<context id="multiline-single-quoted-string" style-ref="multiline-string" class="string" class-disabled="no-spell-check">
+			<start>'''</start>
+			<end>'''</end>
+			<include>
+				<context ref="escaped-char"/>
+			</include>
+		</context>
+
+		<context id="double-quoted-string" style-ref="string" end-at-line-end="true" class="string" class-disabled="no-spell-check">
+			<start>"</start>
+			<end>"</end>
+			<include>
+				<context ref="escaped-char"/>
+				<context ref="def:line-continue"/>
+			</include>
+		</context>
+
+		<context id="single-quoted-string" style-ref="string" end-at-line-end="true" class="string" class-disabled="no-spell-check">
+			<start>'</start>
+			<end>'</end>
+			<include>
+				<context ref="escaped-char"/>
+				<context ref="def:line-continue"/>
+			</include>
+		</context>
+
+		<context id="char" style-ref="character" class="string" class-disabled="no-spell-check">
+			<match extended="true">'([^'])'</match>
+		</context>
+
+		<context id="boolean" style-ref="boolean">
+			<prefix>(?&lt;![\w\.])</prefix>
+			<keyword>false</keyword>
+			<keyword>true</keyword>
+		</context>
+
+		<define-regex id="float" extended="true">
+			( (\d+)?\.\d+ | \d+\. ) |
+			( (\d+|(\d+)?\.\d+|\d+\.)[eE][+-]?\d+ )
+		</define-regex>
+
+		<context id="complex" style-ref="complex">
+			<match>(?&lt;![\w\.])(\%{float}|\d+)[jJ]\b</match>
+		</context>
+
+		<context id="float" style-ref="floating-point">
+			<match>(?&lt;![\w\.])\%{float}(?![\w\.])</match>
+		</context>
+
+		<context id="function-definition">
+		</context>
+
+		<context id="class-definition">
+			<match extended="true">
+				(class)
+				\s+
+				(\%{identifier})
+			</match>
+			<include>
+				<context sub-pattern="1" style-ref="keyword"/>
+				<context sub-pattern="2" style-ref="class-name"/>
+			</include>
+		</context>
+
+		<context id="decorator" style-ref="decorator">
+			<match>@\%{identifier-path}</match>
+		</context>
+
+		<context id="keywords" style-ref="keyword">
+			<keyword>if</keyword>
+			<keyword>for</keyword>
+			<keyword>in</keyword>
+			<keyword>while</keyword>
+			<keyword>else</keyword>
+			<keyword>class</keyword>
+
+			<keyword>return</keyword>
+			<keyword>break</keyword>
+			<keyword>continue</keyword>
+			<keyword>import</keyword>
+			<keyword>delete</keyword>
+			<keyword>assert</keyword>
+			<keyword>breakpoint</keyword>
+
+			<keyword>main</keyword>
+			<keyword>exit</keyword>
+
+			<keyword>init</keyword>
+			<keyword>constr</keyword>
+			<keyword>repr</keyword>
+			<keyword>eq</keyword>
+
+			<keyword>const</keyword>
+			<keyword>static</keyword>
+			<keyword>volatile</keyword>
+			<keyword>property</keyword>
+
+			<keyword>is</keyword>
+			<keyword>in</keyword>
+			<keyword>not</keyword>
+			<keyword>and</keyword>
+			<keyword>but</keyword>
+			<keyword>xor</keyword>
+			<keyword>or</keyword>
+			<keyword>isof</keyword>
+			<keyword>to</keyword>
+		</context>
+
+		<context id="reserved-keywords" style-ref="reserved">
+			<keyword>def</keyword>
+			<keyword>try</keyword>
+			<keyword>catch</keyword>
+			<keyword>except</keyword>
+			<keyword>finally</keyword>
+			<keyword>raise</keyword>
+			<keyword>with</keyword>
+			<keyword>yield</keyword>
+		</context>
+
+		<context id="builtin-constants" style-ref="builtin-constant">
+			<prefix>(?&lt;![\w\.])</prefix>
+			<keyword>none</keyword>
+			<keyword>null</keyword>
+		</context>
+
+		<context id="builtin-objects" style-ref="builtin-object">
+			<prefix>(?&lt;![\w\.])</prefix>
+			<keyword>stdio</keyword>
+			<keyword>globals</keyword>
+		</context>
+
+		<context id="builtin-types" style-ref="builtin-type">
+			<prefix>(?&lt;![\w\.])</prefix>
+			<keyword>i8</keyword>
+			<keyword>i16</keyword>
+			<keyword>i32</keyword>
+			<keyword>i64</keyword>
+			<keyword>i128</keyword>
+
+			<keyword>u8</keyword>
+			<keyword>u16</keyword>
+			<keyword>u32</keyword>
+			<keyword>u64</keyword>
+			<keyword>u128</keyword>
+
+			<keyword>f8</keyword>
+			<keyword>f16</keyword>
+			<keyword>f32</keyword>
+			<keyword>f64</keyword>
+			<keyword>f128</keyword>
+
+			<keyword>uf8</keyword>
+			<keyword>uf16</keyword>
+			<keyword>uf32</keyword>
+			<keyword>uf64</keyword>
+			<keyword>uf128</keyword>
+
+			<keyword>int</keyword>
+			<keyword>uint</keyword>
+			<keyword>float</keyword>
+			<keyword>ufloat</keyword>
+			<keyword>bool</keyword>
+			<keyword>byte</keyword>
+			<keyword>char</keyword>
+			<keyword>str</keyword>
+			<keyword>void</keyword>
+
+			<keyword>auto</keyword>
+
+			<keyword>dict</keyword>
+			<keyword>list</keyword>
+			<keyword>map</keyword>
+			<keyword>object</keyword>
+			<keyword>range</keyword>
+			<keyword>set</keyword>
+			<keyword>tuple</keyword>
+		</context>
+
+		<context id="slang" class="no-spell-check">
+			<include>
+				<context ref="def:shebang"/>
+				<context ref="close-comment-outside-comment" style-ref="def:error"/>
+				<context ref="multiline-comment" style-ref="def:comment"/>
+				<context ref="comment" style-ref="def:comment"/>
+				<context ref="multiline-double-quoted-string"/>
+				<context ref="multiline-single-quoted-string"/>
+				<context ref="double-quoted-string"/>
+				<context ref="single-quoted-string"/>
+				<context ref="char"/>
+				<context ref="boolean"/>
+				<context ref="complex"/>
+				<context ref="float"/>
+				<context ref="def:decimal"/>
+				<context ref="def:octal"/>
+				<context ref="def:hexadecimal"/>
+				<context ref="function-definition"/>
+				<context ref="class-definition"/>
+				<context ref="decorator"/>
+				<context ref="keywords"/>
+				<context ref="reserved-keywords"/>
+				<context ref="builtin-constants"/>
+				<context ref="builtin-objects"/>
+				<context ref="builtin-types"/>
+			</include>
+		</context>
+	</definitions>
+</language>
--- a/sld.py
+++ b/sld.py
@@ -0,0 +1,9 @@
+#!/usr/bin/python3
+# Slang .sld parser
+# .sld files are used for definition of built-in, implementation-provided, external and native components.
+
+from .tokens import *
+from utils import *
+
+
+# by Sdore, 2020
--- a/stdlib.py
+++ b/stdlib.py
@@ -1,7 +1,7 @@
 #!/usr/bin/python3
 # Slang stdlib

-from .ast import Signature, Function, Object
+from .ast import Signature, Function, Object, Collection, CallArguments
 from .tokens import *
 from utils import *

@@ -9,15 +9,25 @@ class Builtin(Signature):
 	def __init__(self):
 		pass

+	@classitemget
+	def attrops(cls, optype, attr):
+		if (optype == '.'):
+			try: return getattr(cls, attr)()
+			except AttributeError: raise KeyError()
+		raise KeyError()
+
 	@property
 	def __reprname__(self):
-		return type(self).mro()[1].__name__
+		return first(i.__name__ for i in self.__class__.mro() if i.__name__.startswith('Builtin'))

 	@property
 	def typename(self):
-		return type(self).__name__
+		return self.__class__.__name__

-class BuiltinFunction(Builtin, Function): pass
+class BuiltinFunction(Builtin, Function):
+	@property
+	def name(self):
+		return self.__class__.__name__

 class BuiltinObject(Builtin, Object): pass

@@ -27,84 +37,173 @@ class BuiltinType(Builtin):
 	def __init__(self, *, modifiers: paramset):
 		self.modifiers = modifiers

-class void(BuiltinType): pass
+	def __eq__(self, x):
+		return (super().__eq__(x) or issubclass(x.__class__, self.__class__) or issubclass(self.__class__, x.__class__))
+
+	@staticitemget
+	@instantiate
+	def operators(op, valsig=None, selftype=None):
+		if (valsig is None):
+			if (op in operators[9]): return bool  # unary `not'
+		else:
+			assert (selftype is not None)
+			if (isinstance(valsig, selftype) and op in operators[8]): return bool  # comparisons
+			if (op in operators[10]+operators[11]+operators[12]): return type(valsig)  # binary `and'. `xor', `or'
+		raise KeyError()
+
+class Any(BuiltinType):
+	def __eq__(self, x):
+		return True
+
+class void(BuiltinType):
+	@staticitemget
+	def operators(op, valsig=None):
+		raise KeyError()

 class bool(BuiltinType):
 	@staticitemget
 	@instantiate
 	def operators(op, valsig=None):
+		try: return BuiltinType.operators(op, valsig=valsig, selftype=bool)
+		except KeyError: pass
 		if (valsig is None):
 			if (op in map(UnaryOperator, '+-~')): return int
-			if (op in map(UnaryOperator, ('not', '!'))): return bool
+			if (op == UnaryOperator('!')): return bool
 		raise KeyError()

 class int(BuiltinType):
 	@staticitemget
 	@instantiate
 	def operators(op, valsig=None):
+		try: return BuiltinType.operators(op, valsig=valsig, selftype=int)
+		except KeyError: pass
 		if (valsig is None):
 			if (op in map(UnaryOperator, '+-~')): return int
-			if (op in map(UnaryOperator, ('not', '!'))): return bool
-		if (not isinstance(valsig, (int, float))): raise KeyError()
-		if (op in map(BinaryOperator, ('**', *'+-*'))): return valsig
-		if (op in map(BinaryOperator, ('//', '<<', '>>', *'&^|'))): return int
-		if (op == BinaryOperator('/')): return float
-		if (op == BinaryOperator('to')): return int
+			if (op == UnaryOperator('!')): return bool
+		if (isinstance(valsig, (int, float))):
+			if (op in map(BinaryOperator, ('**', *'+-*'))): return valsig
+			if (op in map(BinaryOperator, ('//', '<<', '>>', *'&^|'))): return int
+			if (op == BinaryOperator('/')): return float
+		if (isinstance(valsig, int)):
+			if (op == BinaryOperator('to')): return range
 		raise KeyError()

 class float(BuiltinType):
 	@staticitemget
 	@instantiate
 	def operators(op, valsig=None):
+		try: return BuiltinType.operators(op, valsig=valsig, selftype=float)
+		except KeyError: pass
 		if (valsig is None):
-			if (op in map(UnaryOperator, ('not', *'!+-'))): return float
-		if (not isinstance(valsig, (int, float))): raise KeyError()
-		if (op in map(BinaryOperator, ('**', *'+-*'))): return float
-		if (op == BinaryOperator('/')): return float
-		if (op == BinaryOperator('//')): return int
+			if (op in map(UnaryOperator, '+-')): return float
+			if (op == UnaryOperator('!')): return bool
+		if (isinstance(valsig, (int, float))):
+			if (op in map(BinaryOperator, ('**', *'+-*'))): return float
+			if (op == BinaryOperator('/')): return float
+			if (op == BinaryOperator('//')): return int
 		raise KeyError()

 class str(BuiltinType):
 	@staticitemget
 	@instantiate
 	def operators(op, valsig=None):
-		if (valsig is None): raise KeyError()
-		if (isinstance(valsig, str) and op == BinaryOperator('+')): return str
-		if (isinstance(valsig, int) and op == BinaryOperator('*')): return str
+		try: return BuiltinType.operators(op, valsig=valsig, selftype=str)
+		except KeyError: pass
+		if (valsig is not None):
+			if (isinstance(valsig, (char, str)) and op == BinaryOperator('+')): return str
+			if (isinstance(valsig, int) and op == BinaryOperator('*')): return str
 		raise KeyError()

 	@staticitemget
 	@instantiate
-	def itemget(keysig):
+	def itemget(keysig, key):
 		if (isinstance(keysig, int)): return char
 		raise KeyError()

+	class rstrip(BuiltinFunction):
+		callargssigstr = "rstrip(char)"
+
+		@staticitemget
+		@instantiate
+		def call(callargssig):
+			if (callargssig.kwargs or callargssig.starkwargs): raise KeyError()
+			return str
+
+	class count(BuiltinFunction):
+		callargssig = "count(char)"
+
+		@staticitemget
+		@instantiate
+		def call(callargssig):
+			if (callargssig.kwargs or callargssig.starkwargs): raise KeyError()
+			return int
+
 class char(BuiltinType):
 	@staticitemget
 	@instantiate
 	def operators(op, valsig=None):
-		if (valsig is None): raise KeyError()
-		if (isinstance(valsig, str) and op == BinaryOperator('+')): return str
-		if (isinstance(valsig, int) and op == BinaryOperator('*')): return str
-		if (isinstance(valsig, (char, int)) and op in map(BinaryOperator, '+-')): return char
+		try: return BuiltinType.operators(op, valsig=valsig, selftype=char)
+		except KeyError: pass
+		if (valsig is not None):
+			if (isinstance(valsig, str) and op in map(BinaryOperator, ('+', 'in'))): return str
+			if (isinstance(valsig, int) and op == BinaryOperator('*')): return str
+			if (isinstance(valsig, (char, int)) and op in map(BinaryOperator, '+-')): return char
 		raise KeyError()

-i8 = i16 = i32 = i64 = i128 = \
-u8 = u16 = u32 = u64 = u128 = int
-f8 = f16 = f32 = f64 = f128 = \
-uf8 = uf16 = uf32 = uf64 = uf128 = float
-# TODO: implement these types
+class i8(int): fmt = 'b'
+class u8(int): fmt = 'B'
+class i16(int): fmt = 'h'
+class u16(int): fmt = 'H'
+class i32(int): fmt = 'i'
+class u32(int): fmt = 'I'
+class i64(int): fmt = 'q'
+class u64(int): fmt = 'Q'
+#class i128(int): fmt = '
+#class u128(int): fmt = '

-class print(BuiltinFunction):
-	callargssigstr = "print(...)"
+#class f8(float): fmt = '
+#class f16(float): fmt = 'e'
+#class f32(float): fmt = 'f'
+#class f64(float): fmt = 'd'
+#class f128(float): fmt = '
+#uf8 = uf16 = uf32 = uf64 = uf128 = float

+class range(BuiltinType):
+	keytype = int
+	valtype = int
+
+	@staticitemget
+	def operators(op, valsig=None):
+		raise KeyError()
+
+class iterable(BuiltinType, Collection): pass
+
+class list(iterable):
+	keytype = int()
+	valtype = Any()
+
+class tuple(iterable):
+	keytype = int()
+	valtype = Any()
+
+class stdio(BuiltinObject):
+	class println(BuiltinFunction):
+		callargssigstr = "println(...)"
+
+		@staticitemget
+		@instantiate
+		def call(callargssig):
+			if (callargssig.kwargs or callargssig.starkwargs): raise KeyError()
+			return void
+
+class _map(BuiltinFunction):
 	@staticitemget
 	@instantiate
 	def call(callargssig):
 		if (callargssig.kwargs or callargssig.starkwargs): raise KeyError()
-		return void
+		return list

-builtin_names = {j.__name__: globals()[j.__name__] for i in map(operator.methodcaller('__subclasses__'), Builtin.__subclasses__()) for j in i}
-builtin_names.update({i: globals()[i] for i in (i+j for j in map(builtins.str, (8, 16, 32, 64, 128)) for i in (*'iuf', 'uf'))})
+builtin_names = {k: v for i in map(allsubclassdict, Builtin.__subclasses__()) for k, v in i.items()}
+builtin_names.update({i: globals()[i] for i in (i+j for j in map(builtins.str, (8, 16, 32, 64, 128)) for i in (*'iuf', 'uf') if i+j in globals())})

-# by Sdore, 2019
+# by Sdore, 2020
--- a/stdlib/io.sld
+++ b/stdlib/io.sld
@@ -0,0 +1,16 @@
+import sld:std:*;
+
+class fd {
+	str read();
+	str read(int n);
+
+	int write(str data);
+}
+
+class stdio {
+	str readln();
+
+	void print(*args);
+
+	void println(*args);
+}
--- a/stdlib/std.sld
+++ b/stdlib/std.sld
@@ -0,0 +1,117 @@
+class void {}
+
+class bool {
+	castable to int;
+
+	bool operator !;
+}
+
+class int {
+	castable to bool;
+	castable to float;
+
+	int operator +;
+	int operator -;
+	int operator ~;
+
+	int operator +int;
+	int operator -int;
+	int operator *int;
+	int operator //int;
+	int operator **int;
+	int operator <<int;
+	int operator >>int;
+	int operator &int;
+	int operator ^int;
+	int operator |int;
+
+	range operator to int;
+
+	int popcount();
+	int length(int base=2);
+}
+
+class float {
+	float operator +;
+	float operator -;
+	bool operator !;
+
+	float operator +float;
+	float operator -float;
+	float operator *float;
+	float operator /float;
+	int operator //float;
+	float operator **float;
+
+	int round();
+	bool isint();
+}
+
+class char {
+	castable to str;
+
+	bool operator !;
+
+	char operator +char;
+	char operator +int;
+	char operator -char;
+	char operator -int;
+	char operator *int;
+
+	range operator 'to' char;
+}
+
+class str {
+	bool operator !;
+
+	iterable char;
+
+	char operator [int];
+
+	str operator +str;
+	str operator *int;
+}
+
+class range {
+	typename type;
+
+	iterable type;
+
+	type operator [int];
+}
+
+class list {
+	typename type;
+
+	iterable type;
+
+	type operator [int];
+
+	void append(type item);
+
+	void insert(int index, type item);
+
+	type pop();
+	type pop(int index);
+
+	void reverse();
+
+	void sort();
+}
+
+class tuple {
+	typename types[];
+
+	iterable types;
+
+	types operator [int];
+}
+
+class function {
+	typename argtypes[];
+	typename rettype;
+
+	call rettype (*argtypes);
+
+	rettype map(iterable);
+}
--- a/tests/class.sl
+++ b/tests/class.sl
@@ -0,0 +1,37 @@
+class Test {
+	int a = 1
+
+	init {
+		.a = 3
+	}
+
+	constr () {
+		.a = 5
+	}
+
+	constr (int a) {
+		.a = a
+	}
+}
+
+main {
+	stdio.println(Test.a)
+
+	Test t
+	stdio.println(t.a)
+	t.a = 2
+	stdio.println(t.a)
+	delete t
+
+	Test t = Test()
+	stdio.println(t.a)
+	delete t
+
+	Test t = Test(7)
+	stdio.println(t.a)
+	delete t
+
+	#Test t(10)
+	#stdio.println(t.a)
+	#delete t
+}
--- a/tests/example.sl
+++ b/tests/example.sl
@@ -18,10 +18,8 @@ auto g(str x) {  # g() is of type char, x is of type str

 int h(int x) = x+1  # h() is of type int, x is of type int

-void main() {
-	print(h(n), \
+main {
+	stdio.println(h(n), \  # comment here too
 		f('123asd') + g('32') + 1)  #--> «123124 f»
-	print(q/z/2**96)  #--> «4294967296.0»
+	stdio.println(q/z/2**96)  #--> «4294967296.0»
 }
-
-main()
--- a/tests/fib.sl
+++ b/tests/fib.sl
@@ -0,0 +1,8 @@
+int fib(int n) {
+	if (n < 2) {return 1}
+	return fib(n-1) + fib(n-2)
+}
+
+main {
+	stdio.println(fib(3))
+}
--- a/tests/fmap.sl
+++ b/tests/fmap.sl
@@ -0,0 +1,5 @@
+void f(int x) = stdio.println(x)
+
+main {
+	f.map([int: 1, 2, 3])
+}
--- a/tests/for.sl
+++ b/tests/for.sl
@@ -0,0 +1,6 @@
+main {
+	for i in (0 to 5) {
+		stdio.println(i)
+		stdio.println(i+2)
+	}
+}
--- a/tests/funcdef.sl
+++ b/tests/funcdef.sl
@@ -1,2 +1,2 @@
 void f() {}
-void f(int a?) {}
+void f(int a?) {}
--- a/tests/list.sl
+++ b/tests/list.sl
@@ -0,0 +1,10 @@
+list l = [int: 1, 2, 3]
+
+main {
+	#int i = 0
+	#while (i < 3) {
+	for i in (0 to 3) {
+		stdio.println(i, l[i])
+		#i -=- 1
+	}
+}
--- a/tests/nl.sl
+++ b/tests/nl.sl
@@ -0,0 +1,4 @@
+main {
+	stdio.println(1, #|
+		|# 2)
+}
--- a/tests/opti.sl
+++ b/tests/opti.sl
@@ -1,2 +1,5 @@
 int a = 3
-print(2**a)
+
+main {
+	stdio.println(2**a)
+}
--- a/tests/overload.sl
+++ b/tests/overload.sl
@@ -1,5 +1,7 @@
 int f(int x) = x+1
 int f(int x, int y) = x+y+1

-print(f(1))
-print(f(1, 2))
+main {
+	stdio.println(f(1))
+	stdio.println(f(1, 2))
+}
--- a/tests/println.sl
+++ b/tests/println.sl
@@ -0,0 +1,3 @@
+main {
+	stdio.println('test')
+}
--- a/tests/redefine.sl
+++ b/tests/redefine.sl
@@ -0,0 +1,6 @@
+main {
+	int a
+	a = 3
+	a, b := (int a, char 'b')
+	stdio.println(a, b)
+}
--- a/tests/strcat.sl
+++ b/tests/strcat.sl
@@ -0,0 +1,4 @@
+str a = "a"
+str b = "B"
+str c = a+b
+stdio.println(c)
--- a/tests/sum.sl
+++ b/tests/sum.sl
@@ -1,3 +1,4 @@
-int a = 3
-int b = 5
-print(a+b)
+i8 a = 3
+i8 b = 5
+i8 c = a+b
+stdio.println(c)
--- a/tests/test.sl
+++ b/tests/test.sl
@@ -2,29 +2,27 @@ const int a = 3
 int b = 2; int c = 0; int x = 9

 int sum(int a, int z) = a + z
-print(sum(a, b & 3))
-print(1)
-print(1, 2)
-print('a')
-print(2*(3)+-2*(5+1)/2)
-print(-2*x**(2+2)*a*b+10*c)
-print(*'a'+'b'*2)
-print(-2-2-2-2-2-2-2-2)
+stdio.println(sum(a, b & 3))
+stdio.println(1)
+stdio.println(1, 2)
+stdio.println('a')
+stdio.println(2*(3)+-2*(5+1)/2)
+stdio.println(-2*x**(2+2)*a*b+10*c)
+stdio.println(*'a'+'b'*2)
+stdio.println(-2-2-2-2-2-2-2-2)

-void main() {
+main {
 	int z = sum(3, 2)
 	b = 2**100
 	b *= 2
-	print(not a)
-	print(a, b, c)
+	stdio.println(not a)
+	stdio.println(a, b, c)
 	int test() = 2*2
-	print(sum(b, test()))
+	stdio.println(sum(b, test()))

-	for i in (0 to 5) print(i)
-	else print(0)
+	for i in 0 to 5 stdio.println(i)
+	else stdio.println(0)

 	int i = 5
-	while (i) {print(i); i -= 1;} else print('ВСЁ!')
+	while i {stdio.println(i); i -= 1;} else stdio.println('ВСЁ!')
 }
-
-main()
--- a/tests/wrongnl.sl
+++ b/tests/wrongnl.sl
@@ -0,0 +1,4 @@
+main {
+	stdio.println(1, \ 2,
+		3)
+}
--- a/tokens.py
+++ b/tokens.py
@@ -5,12 +5,19 @@ from utils import *

 class Keyword(str): pass
 class ExprKeyword(Keyword): pass
+class DefKeyword(Keyword): pass
+class DefNamedKeyword(Keyword): pass
+class DefArgsKeyword(Keyword): pass
+class ClassdefKeyword(DefKeyword): pass # TODO validate!
+class ClassdefNamedKeyword(ClassdefKeyword, DefNamedKeyword): pass
+class ClassdefArgsKeyword(ClassdefKeyword, DefArgsKeyword): pass
 class Modifier(Keyword): pass
 class ReservedKeyword(Keyword): pass

 class Operator(str): pass
 class UnaryOperator(Operator): pass
 class BinaryOperator(Operator): pass
+class BothOperator(UnaryOperator, BinaryOperator): pass

 keywords = (
 	Keyword('if'),
@@ -18,17 +25,36 @@ keywords = (
 	Keyword('in'),
 	Keyword('while'),
 	Keyword('else'),
+	Keyword('class'),
 	ExprKeyword('return'),
 	ExprKeyword('break'),
 	ExprKeyword('continue'),
 	ExprKeyword('import'),
+	ExprKeyword('delete'),
+	ExprKeyword('assert'),
+	ExprKeyword('breakpoint'),
+	DefKeyword('main'),
+	DefKeyword('exit'),
+	ClassdefKeyword('init'),
+	ClassdefArgsKeyword('constr'),
+	ClassdefNamedKeyword('property'),
+	ClassdefKeyword('repr'),
+	ClassdefKeyword('eq'),
 	Modifier('const'),
+	Modifier('static'),
 	Modifier('volatile'),
 	ReservedKeyword('def'),
+	ReservedKeyword('try'),
+	ReservedKeyword('catch'),
+	ReservedKeyword('except'),
+	ReservedKeyword('finally'),
+	ReservedKeyword('raise'),
+	ReservedKeyword('with'),
+	ReservedKeyword('yield'),
 )

-operators = (*(tuple(map(*i)) for i in ( # ordered by priority
-	(UnaryOperator, '!$:~'),
+operators = (*(tuple(map(*i)) for i in (  # ordered by priority
+	(UnaryOperator, '!+-~'),
 	(BinaryOperator, ('**',)),
 	(BinaryOperator, ('//', *'*/%')),
 	(BinaryOperator, '+-'),
@@ -36,19 +62,19 @@ operators = (*(tuple(map(*i)) for i in ( # ordered by priority
 	(BinaryOperator, '&'),
 	(BinaryOperator, '^'),
 	(BinaryOperator, '|'),
-	(BinaryOperator, ('<', '<=', '>', '>=', '==', '!=', 'is not', 'is')),
+	(BinaryOperator, ('<', '<=', '>', '>=', '==', '!=', 'is', 'is not', 'in', 'not in', 'isof')),
 	(UnaryOperator, ('not',)),
-	(BinaryOperator, ('&&', 'and')),
+	(BinaryOperator, ('&&', 'and', 'but')),
 	(BinaryOperator, ('^^', 'xor')),
 	(BinaryOperator, ('||', 'or')),
 	(BinaryOperator, ('to',)),
 )),)
-bothoperators = '%&*+-^'
+bothoperators = '+-'
 attrops = ('->', '@.', *'@.:')
-keyword_operators = ('is not', 'is', 'not', 'and', 'xor', 'or', 'to')
+logical_operators = ('is', 'is not', 'in', 'not in', 'not', 'and', 'but', 'xor', 'or', 'isof')

 whitespace = ' \t\r\v\f'
-specials = ('..', '->', '@.', *'#@.\\,;?=()[]{}')
+specials = ('..', ':=', *attrops, *r'#\,;?=()[]{}')

 def find_identifier(s):
 	if (not s or not s[0].isidentifier()): return
@@ -63,7 +89,7 @@ def find_keyword(s):
 	for i in keywords:
 		if (s.startswith(i)):
 			l = len(i)
-			if (not s[l:l+1] or s[l:l+1].isspace()): return (l, i)
+			if (not s[l:l+1].isidentifier()): return (l, i)

 def find_literal(s):
 	if (not s): return
@@ -78,7 +104,7 @@ def find_literal(s):
 		digits = '0123456789abcdef'
 		radix = 10
 		digit = True
-		dp = s[0] == '.'
+		dp = (s[0] == '.')
 		for i in range(1, len(s)):
 			if (i == 1 and s[0] == '0'):
 				if (s[1] not in 'box'):
@@ -94,14 +120,14 @@ def find_literal(s):
 				if (not digit or s[i].isalpha()): return
 				return i
 			digit = True
-		if (s[i].casefold() in digits[:radix] or s[i] == '.' and not dp): return i+1
+		if (s[i].casefold() in digits[:radix] or s[i] == '.' and dp): return i+1

 def find_operator(s):
 	if (not s): return
 	for i in sorted(itertools.chain(*operators), key=len, reverse=True):
 		if (s.startswith(i)):
 			l = len(i)
-			if (not (i[-1].isalpha() and s[l:l+1].isalnum())): return (len(i), i)
+			if (not (i[-1].isalpha() and s[l:l+1].isidentifier())): return (len(i), BothOperator(i) if (i in bothoperators) else i)

 def find_special(s):
 	if (not s): return
@@ -114,7 +140,7 @@ def find_special(s):
 		l = s.find('\n', 1)
 		if (l == -1): return len(s)
 		return l
-	if (s[:2] == '\\\n'): return 2
+	if (s[0] == '\\'): return 1
 	for i in sorted(specials, key=len, reverse=True):
 		if (s[:len(i)] == i):
 			if (i == '=' and s[:len(i)+1] == '=='): break
@@ -127,7 +153,7 @@ def operator_precedence(op):

 class Token:
 	__slots__ = ('type', 'token', 'lineno', 'offset')
-	types = ('SPECIAL', 'OPERATOR', 'LITERAL', 'KEYWORD', 'IDENTIFIER') # order is also resolution order
+	types = ('SPECIAL', 'OPERATOR', 'LITERAL', 'KEYWORD', 'IDENTIFIER')  # order is also resolution order

 	def __init__(self, type, token, *, lineno, offset):
 		self.type, self.token, self.lineno, self.offset = type, token, lineno, offset
@@ -157,11 +183,12 @@ class SlSyntaxNoToken(SlSyntaxException): pass
 class SlSyntaxEmpty(SlSyntaxNoToken): pass

 class SlSyntaxError(SlSyntaxException):
-	__slots__ = ('desc', 'line', 'lineno', 'offset', 'length')
+	__slots__ = ('desc', 'line', 'lineno', 'offset', 'length', 'usage')

 	#@dispatch
 	def __init__(self, desc='Syntax error', line='', *, lineno, offset, length, scope=None):
 		self.desc, self.line, self.lineno, self.offset, self.length = (f'\033[2m(in {scope})\033[0m ' if (scope is not None) else '')+desc, line, lineno, offset, length
+		self.usage = None

 	#@dispatch
 	#def __init__(self, desc='Syntax error', *, token):
@@ -169,10 +196,12 @@ class SlSyntaxError(SlSyntaxException):

 	def __str__(self):
 		l, line = lstripcount(self.line.partition('\n')[0].replace('\t', ' '), ' \t')
-		offset = (self.offset-l) if (self.offset != -1) else len(line)
+		offset = (self.offset-l) if (self.offset >= 0) else (len(line)+self.offset+1)
+		#Syntax error: 
 		return f"{self.desc}{self.at}"+(':\n'+\
-			'  \033[1m'+line[:offset]+'\033[91m'+line[offset:]+'\033[0m\n'+\
-			'  '+' '*offset+'\033[95m^'+'~'*(self.length-1) if (line) else '')
+			'  \033[1m'+line[:offset]+'\033[91m'*(self.offset >= 0)+line[offset:]+'\033[0m\n'+\
+			'  '+' '*offset+'\033[95m^'+'~'*(self.length-1)+'\033[0m' if (line) else '') + \
+			(f"\n\n\033[1;95mCaused by:\033[0m\n{self.__cause__}" if (self.__cause__ is not None) else '')

 	@property
 	def at(self):
@@ -182,25 +211,57 @@ class SlSyntaxExpectedError(SlSyntaxError):
 	__slots__ = ('expected', 'found')

 	def __init__(self, expected='nothing', found='nothing', *, lineno=None, offset=None, length=0, scope=None):
-		assert expected != found
+		assert (expected != found)
 		if (not isinstance(found, str)): lineno, offset, length, found = found.lineno, found.offset, found.length, found.typename if (hasattr(found, 'typename')) else found
-		assert lineno is not None and offset is not None
+		assert (lineno is not None and offset is not None)
 		super().__init__(f"Expected {expected.lower()},\n{' '*(len(scope)+6 if (scope is not None) else 3)}found {found.lower()}", lineno=lineno, offset=offset, length=length, scope=scope)
 		self.expected, self.found = expected, found

 class SlSyntaxExpectedNothingError(SlSyntaxExpectedError):
-	def __init__(self, found='nothing', **kwargs):
+	def __init__(self, found, **kwargs):
 		super().__init__(found=found, **kwargs)

-class SlSyntaxMultiExpectedError(SlSyntaxExpectedError):
-	__slots__ = ('sl',)
+class SlSyntaxExpectedMoreTokensError(SlSyntaxExpectedError):
+	def __init__(self, for_, *, offset=-1, **kwargs):
+		assert (offset < 0)
+		super().__init__(expected=f"More tokens for {for_}", offset=offset, **kwargs)

-	def __init__(self, expected, found, *, scope=None, **kwargs):
+class SlSyntaxMultiExpectedError(SlSyntaxExpectedError):
+	__slots__ = ('sl', 'errlist')
+
+	def __init__(self, expected, found, *, scope=None, errlist=None, **kwargs):
+		self.errlist = errlist
 		self.sl = len(scope)+6 if (scope is not None) else 0
-		super().__init__(S(',\n'+' '*(self.sl+9)).join(Stuple(expected).strip('nothing').uniquize(), last=',\n'+' '*(self.sl+6)+'or ') or 'nothing', S(',\n'+' '*(self.sl+6)).join(Stuple(f"{i.found} at offset {i.offset if (i.offset != -1) else '<end of line>'}" for i in found).strip('nothing').uniquize(), last=',\n'+' '*(self.sl+2)+'and ') or 'nothing', scope=scope, **kwargs)
+		super().__init__(
+			expected=S(',\n'+' '*(self.sl+9)).join(Stuple((i.expected+f" at offset {i.offset if (i.offset >= 0) else '<end of line>'}{i.offset+1 if (i.offset < -1) else ''}" if (not isinstance(i, SlSyntaxMultiExpectedError)) else i.expected)+(f' (for {i.usage})' if (i.usage) else '') for i in expected).strip('nothing').uniquize(str.casefold), last=',\n'+' '*(self.sl+6)+'or ') or 'nothing',
+			found=S(',\n'+' '*(self.sl+6)).join(Stuple(i.found+f" at {f'offset {i.offset}' if (i.offset >= 0) else '<end of line>'}{i.offset+1 if (i.offset < -1) else ''}" if (not isinstance(i, SlSyntaxMultiExpectedError)) else i.expected for i in found).strip('nothing').uniquize(str.casefold), last=',\n'+' '*(self.sl+2)+'and ') or 'nothing',
+			scope=scope,
+			**kwargs
+		)

 	@property
 	def at(self):
 		return f"\n{' '*self.sl}at line {self.lineno}"

-# by Sdore, 2019
+	@classmethod
+	def from_list(cls, err, scope=None, **kwargs):
+		sl = len(scope)+6 if (scope is not None) else 0
+
+		for i in err:
+			if (isinstance(i, SlSyntaxMultiExpectedError)):
+				loff = 0
+				i.expected = ' '*loff+S(i.expected).indent(sl+loff).lstrip()
+				i.found = ' '*loff+S(i.found).indent(sl+loff).lstrip()
+
+		return cls(
+			expected=sorted(err, key=operator.attrgetter('expected'), reverse=True),
+			found=sorted(err, key=operator.attrgetter('offset')),
+			lineno=max(err, key=operator.attrgetter('lineno')).lineno,
+			offset=max(err, key=lambda x: x.offset if (x.offset >= 0) else inf).offset,
+			length=min(i.length for i in err if i.length) if (not any(i.offset < 0 for i in err)) else 0,
+			scope=scope,
+			errlist=list(err),
+			**kwargs
+		)
+
+# by Sdore, 2020