fixes and destructure

Cargo.lock

@@ -326,9 +326,9 @@ dependencies = [
 
 [[package]]
 name = "quote"
-version = "1.0.37"
+version = "1.0.38"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b5b9d34b8991d19d98081b46eacdd8eb58c6f2b201139f7c5f643cc155a633af"
+checksum = "0e4dccaaaf89514f546c693ddc140f729f958c247918a13380cccc6078391acc"
 dependencies = [
  "proc-macro2",
 ]
@@ -445,9 +445,9 @@ checksum = "3c5e1a9a646d36c3599cd173a41282daf47c44583ad367b8e6837255952e5c67"
 
 [[package]]
 name = "syn"
-version = "2.0.91"
+version = "2.0.93"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d53cbcb5a243bd33b7858b1d7f4aca2153490815872d86d955d6ea29f743c035"
+checksum = "9c786062daee0d6db1132800e623df74274a0a87322d8e183338e01b3d98d058"
 dependencies = [
  "proc-macro2",
  "quote",

talc-lang/src/chunk.rs

@@ -1,5 +1,5 @@
 use crate::{
-	parser::ast::{BinaryOp, UnaryOp},
+	ops::{BinaryOp, UnaryOp},
 	symbol::Symbol,
 	value::Value,
 };
@@ -139,8 +139,11 @@ pub enum Instruction {
 	GrowTable(u8),
 	ExtendTable,
 
+	ListDestructure(u8, u8, bool),
+
 	Index,
 	StoreIndex,
+	StoreIndexOp(BinaryOp),
 
 	Jump(Arg24),
 	JumpTrue(Arg24),
@@ -195,16 +198,20 @@ impl std::fmt::Display for Instruction {
 			Self::DupTwo => write!(f, "duptwo"),
 			Self::Drop => write!(f, "drop"),
 			Self::Swap => write!(f, "swap"),
-			Self::UnaryOp(o) => write!(f, "unary {o:?}"),
+			Self::UnaryOp(o) => write!(f, "unary {o}"),
-			Self::BinaryOp(o) => write!(f, "binary {o:?}"),
+			Self::BinaryOp(o) => write!(f, "binary {o}"),
 			Self::NewList(n) => write!(f, "newlist #{n}"),
 			Self::GrowList(n) => write!(f, "growlist #{n}"),
 			Self::ExtendList => write!(f, "extendlist"),
 			Self::NewTable(n) => write!(f, "newtable #{n}"),
 			Self::GrowTable(n) => write!(f, "growtable #{n}"),
+			Self::ListDestructure(l, r, interp) => {
+				write!(f, "listdestructure #{l},#{r},{interp}")
+			}
 			Self::ExtendTable => write!(f, "extendtable"),
 			Self::Index => write!(f, "index"),
 			Self::StoreIndex => write!(f, "storeindex"),
+			Self::StoreIndexOp(o) => write!(f, "storeindexop {o}"),
 			Self::Jump(a) => write!(f, "jump @{}", usize::from(a)),
 			Self::JumpTrue(a) => write!(f, "jumptrue @{}", usize::from(a)),
 			Self::JumpFalse(a) => write!(f, "jumpfalse @{}", usize::from(a)),

talc-lang/src/compiler.rs

@@ -3,14 +3,15 @@ use std::collections::HashMap;
 use std::rc::Rc;
 
 use crate::chunk::{Arg24, Catch, Chunk, Instruction as I};
+use crate::ops::BinaryOp;
 use crate::parser::ast::{
-	BinaryOp, CatchBlock, Expr, ExprKind, LValue, LValueKind, ListItem, TableItem,
+	CatchBlock, Expr, ExprKind, LValue, LValueKind, ListItem, TableItem,
 };
 use crate::parser::Pos;
-use crate::prelude::*;
 use crate::symbol::{Symbol, SYM_REPL, SYM_SELF};
 use crate::value::function::{FuncAttrs, Function};
 use crate::value::Value;
+use crate::{prelude::*, throw};
 
 #[derive(Clone, Debug)]
 pub struct CompileError {
@@ -222,6 +223,7 @@ impl<'a> Compiler<'a> {
 			) => {
 				// final side-effectless instruction
 				instrs.pop().unwrap();
+				return
 			}
 			Some(
 				I::NewLocal
@@ -236,13 +238,13 @@ impl<'a> Compiler<'a> {
 					let i = self.chunk.instrs.pop().unwrap();
 					self.chunk.instrs.pop().unwrap();
 					self.chunk.instrs.push(i);
+					return
 				}
 			}
-			_ => {
+			_ => (),
+		}
 		self.emit(I::Drop);
 	}
-		}
-	}
 
 	fn ip(&self) -> usize {
 		self.chunk.instrs.len()
@@ -370,6 +372,10 @@ impl<'a> Compiler<'a> {
 		Ok(())
 	}
 
+	fn load_global(&mut self, name: Symbol) {
+		self.emit(I::LoadGlobal(Arg24::from_symbol(name)));
+	}
+
 	fn declare_local(&mut self, name: Symbol) -> usize {
 		let local = VarKind::Local(self.local_count);
 		self.local_count += 1;
@@ -452,6 +458,11 @@ impl<'a> Compiler<'a> {
 			}
 			ExprKind::Literal(v) => self.expr_literal(v),
 			ExprKind::Ident(ident) => self.load_var(*ident)?,
+			ExprKind::Var(_) => throw!(
+				span.start,
+				"identifer qualified with var can only be used as an lvalue"
+			),
+			ExprKind::Global(ident) => self.load_global(*ident),
 			ExprKind::UnaryOp(o, a) => {
 				self.expr(a)?;
 				self.emit(I::UnaryOp(*o));
@@ -462,24 +473,6 @@ impl<'a> Compiler<'a> {
 				self.emit(I::BinaryOp(*o));
 			}
 			ExprKind::Assign(o, lv, a) => self.expr_assign(*o, lv, a)?,
-			ExprKind::AssignVar(name, a) => {
-				if let Some(a) = a {
-					self.expr(a)?;
-				} else {
-					self.emit(I::Nil);
-				}
-				self.emit(I::Dup);
-				self.assign_local(*name);
-			}
-			ExprKind::AssignGlobal(name, a) => {
-				if let Some(a) = a {
-					self.expr(a)?;
-					self.emit(I::Dup);
-					self.assign_global(*name);
-				} else {
-					self.declare_global(*name);
-				}
-			}
 			ExprKind::List(xs) => self.expr_list(xs)?,
 			ExprKind::Table(xs) => self.expr_table(xs)?,
 			ExprKind::Index(ct, idx) => {
@@ -855,34 +848,84 @@ impl<'a> Compiler<'a> {
 		self.emit(I::Const(Arg24::from_usize(n)));
 	}
 
-	fn expr_assign(&mut self, o: Option<BinaryOp>, lv: &LValue, a: &Expr) -> Result<()> {
+	fn lvalue(&mut self, lv: &LValue) -> Result<()> {
-		match (&lv.kind, o) {
+		match &lv.kind {
-			(LValueKind::Ident(i), None) => {
+			LValueKind::Ident(i) => {
-				self.expr(a)?;
 				self.emit(I::Dup);
 				self.store_var(*i);
 			}
-			(LValueKind::Ident(i), Some(o)) => {
+			LValueKind::Var(i) => {
+				self.emit(I::Dup);
+				self.assign_local(*i);
+			}
+			LValueKind::Global(i) => {
+				self.emit(I::Dup);
+				self.assign_global(*i);
+			}
+			LValueKind::Index(ct, i) => {
+				self.expr(ct)?;
+				self.expr(i)?;
+				self.emit(I::StoreIndex);
+			}
+			LValueKind::List(ls, i) => {
+				let Ok(len) = u8::try_from(ls.len()) else {
+					throw!(lv.span.start, "list destructure is too large");
+				};
+
+				self.emit(I::Dup);
+
+				let i = i.map(|n| u8::try_from(n).expect("interp index past end of list?"));
+
+				self.emit(I::ListDestructure(
+					i.unwrap_or(len),
+					i.map(|n| len - n - 1).unwrap_or(0),
+					i.is_some(),
+				));
+
+				for lv in ls {
+					self.lvalue(lv)?;
+					self.emit_discard();
+				}
+			}
+		}
+		Ok(())
+	}
+
+	fn expr_assign(&mut self, o: Option<BinaryOp>, lv: &LValue, a: &Expr) -> Result<()> {
+		let Some(o) = o else {
+			self.expr(a)?;
+			self.lvalue(lv)?;
+			return Ok(())
+		};
+		match &lv.kind {
+			LValueKind::Ident(i) => {
 				self.load_var(*i)?;
 				self.expr(a)?;
 				self.emit(I::BinaryOp(o));
 				self.emit(I::Dup);
 				self.store_var(*i);
 			}
-			(LValueKind::Index(ct, i), None) => {
+			LValueKind::Var(_) => {
-				self.expr(ct)?;
+				throw!(lv.span.start, "cannot compound assign to explicit local")
-				self.expr(i)?;
-				self.expr(a)?;
-				self.emit(I::StoreIndex);
 			}
-			(LValueKind::Index(ct, i), Some(o)) => {
+			LValueKind::Global(i) => {
-				self.expr(ct)?;
+				self.load_global(*i);
-				self.expr(i)?;
-				self.emit(I::DupTwo);
-				self.emit(I::Index);
 				self.expr(a)?;
 				self.emit(I::BinaryOp(o));
-				self.emit(I::StoreIndex);
+				self.emit(I::Dup);
+				self.assign_global(*i);
+			}
+			LValueKind::Index(ct, i) => {
+				self.expr(a)?;
+				self.expr(ct)?;
+				self.expr(i)?;
+				self.emit(I::StoreIndexOp(o));
+			}
+			LValueKind::List(..) => {
+				throw!(
+					lv.span.start,
+					"cannot compound assign to a list destructure"
+				)
 			}
 		}
 		Ok(())

talc-lang/src/lib.rs

@@ -9,6 +9,7 @@ pub mod compiler;
 pub mod exception;
 pub mod lstring;
 pub mod number;
+pub mod ops;
 pub mod optimize;
 pub mod parser;
 pub mod serial;

talc-lang/src/lstring.rs

@@ -151,30 +151,40 @@ pub struct LStr {
 	inner: [u8],
 }
 
-impl fmt::Debug for LStr {
+impl LStr {
-	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+	pub fn to_escaped(&self) -> String {
-		f.write_char('"')?;
+		let mut s = String::new();
+		s += "\"";
 		let mut bytes = &self.inner;
 		while let Some((new_bytes, res)) = next_codepoint(bytes) {
 			bytes = new_bytes;
 			match res {
-				Ok('"') => f.write_str("\\\"")?,
+				Ok('"') => s += "\\\"",
-				Ok('\\') => f.write_str("\\\\")?,
+				Ok('\\') => s += "\\\\",
-				Ok('\x00') => f.write_str("\\0")?,
+				Ok('\x00') => s += "\\0",
-				Ok('\x07') => f.write_str("\\a")?,
+				Ok('\x07') => s += "\\a",
-				Ok('\x08') => f.write_str("\\b")?,
+				Ok('\x08') => s += "\\b",
-				Ok('\x09') => f.write_str("\\t")?,
+				Ok('\x09') => s += "\\t",
-				Ok('\x0a') => f.write_str("\\n")?,
+				Ok('\x0a') => s += "\\n",
-				Ok('\x0b') => f.write_str("\\v")?,
+				Ok('\x0b') => s += "\\v",
-				Ok('\x0c') => f.write_str("\\f")?,
+				Ok('\x0c') => s += "\\f",
-				Ok('\x0d') => f.write_str("\\r")?,
+				Ok('\x0d') => s += "\\r",
-				Ok('\x1b') => f.write_str("\\e")?,
+				Ok('\x1b') => s += "\\e",
-				Ok(c) if c.is_control() => write!(f, "\\u{{{:x}}}", c as u32)?,
+				Ok(c) if c.is_control() => {
-				Ok(c) => f.write_char(c)?,
+					write!(s, "\\u{{{:x}}}", c as u32).expect("failed to write to string");
-				Err(b) => write!(f, "\\x{b:02x}")?,
+				}
+				Ok(c) => s.push(c),
+				Err(b) => write!(s, "\\x{b:02x}").expect("failed to write to string"),
 			}
 		}
-		f.write_char('"')
+		s += "\"";
+		s
+	}
+}
+
+impl fmt::Debug for LStr {
+	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+		f.write_str(&self.to_escaped())
 	}
 }
 

talc-lang/src/ops.rs

@@ -0,0 +1,91 @@
+use std::fmt;
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub enum BinaryOp {
+	Add,
+	Sub,
+	Mul,
+	Div,
+	Mod,
+	Pow,
+	IntDiv,
+	Shr,
+	Shl,
+	BitAnd,
+	BitXor,
+	BitOr,
+	Eq,
+	Ne,
+	Gt,
+	Lt,
+	Ge,
+	Le,
+	Concat,
+	Append,
+	Range,
+	RangeIncl,
+}
+
+impl BinaryOp {
+	pub fn name(self) -> &'static str {
+		match self {
+			Self::Add => "add",
+			Self::Sub => "sub",
+			Self::Mul => "mul",
+			Self::Div => "div",
+			Self::Mod => "mod",
+			Self::Pow => "pow",
+			Self::IntDiv => "int_div",
+			Self::Shr => "shr",
+			Self::Shl => "shl",
+			Self::BitAnd => "bit_and",
+			Self::BitXor => "bit_xor",
+			Self::BitOr => "bit_or",
+			Self::Eq => "eq",
+			Self::Ne => "ne",
+			Self::Gt => "gt",
+			Self::Lt => "lt",
+			Self::Ge => "ge",
+			Self::Le => "le",
+			Self::Concat => "concat",
+			Self::Append => "append",
+			Self::Range => "range",
+			Self::RangeIncl => "range_incl",
+		}
+	}
+}
+
+impl fmt::Display for BinaryOp {
+	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+		f.write_str(self.name())
+	}
+}
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub enum UnaryOp {
+	Neg,
+	Not,
+	BitNot,
+	RangeFrom,
+	RangeTo,
+	RangeToIncl,
+}
+
+impl UnaryOp {
+	pub fn name(self) -> &'static str {
+		match self {
+			UnaryOp::Neg => "neg",
+			UnaryOp::Not => "not",
+			UnaryOp::BitNot => "bit_not",
+			UnaryOp::RangeFrom => "range_from",
+			UnaryOp::RangeTo => "range_to",
+			UnaryOp::RangeToIncl => "range_to_incl",
+		}
+	}
+}
+
+impl fmt::Display for UnaryOp {
+	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+		f.write_str(self.name())
+	}
+}

talc-lang/src/optimize.rs

@@ -52,6 +52,8 @@ fn optimize_ex_with(expr: &mut Expr, state: OptState) {
 	match &mut expr.kind {
 		ExprKind::Literal(_) => (),
 		ExprKind::Ident(_) => (),
+		ExprKind::Var(_) => (),
+		ExprKind::Global(_) => (),
 		ExprKind::UnaryOp(o, e) => {
 			optimize_ex(e);
 			if let Some(a) = e.value() {
@@ -73,16 +75,6 @@ fn optimize_ex_with(expr: &mut Expr, state: OptState) {
 			optimize_lv(l);
 			optimize_ex(r);
 		}
-		ExprKind::AssignVar(_, e) => {
-			if let Some(e) = e {
-				optimize_ex(e);
-			}
-		}
-		ExprKind::AssignGlobal(_, e) => {
-			if let Some(e) = e {
-				optimize_ex(e);
-			}
-		}
 		ExprKind::FnDef(_, _, e) => {
 			optimize_ex_with(e, OptState::ret(true));
 		}
@@ -227,10 +219,17 @@ fn optimize_ex_with(expr: &mut Expr, state: OptState) {
 fn optimize_lv(e: &mut LValue) {
 	match &mut e.kind {
 		LValueKind::Ident(_) => (),
+		LValueKind::Var(_) => (),
+		LValueKind::Global(_) => (),
 		LValueKind::Index(l, r) => {
 			optimize_ex(l);
 			optimize_ex(r);
 		}
+		LValueKind::List(ls, _) => {
+			for l in ls {
+				optimize_lv(l);
+			}
+		}
 	}
 }
 

talc-lang/src/parser/ast.rs

@@ -1,45 +1,13 @@
 use core::fmt;
 
-use crate::{symbol::Symbol, value::Value};
+use crate::{
+	ops::{BinaryOp, UnaryOp},
+	symbol::Symbol,
+	value::Value,
+};
 
 use super::Span;
 
-#[derive(Clone, Copy, Debug, PartialEq, Eq)]
-pub enum BinaryOp {
-	Add,
-	Sub,
-	Mul,
-	Div,
-	Mod,
-	Pow,
-	IntDiv,
-	Shr,
-	Shl,
-	BitAnd,
-	BitXor,
-	BitOr,
-	Eq,
-	Ne,
-	Gt,
-	Lt,
-	Ge,
-	Le,
-	Concat,
-	Append,
-	Range,
-	RangeIncl,
-}
-
-#[derive(Clone, Copy, Debug, PartialEq, Eq)]
-pub enum UnaryOp {
-	Neg,
-	Not,
-	BitNot,
-	RangeFrom,
-	RangeTo,
-	RangeToIncl,
-}
-
 #[derive(Debug)]
 pub struct Expr {
 	pub span: Span,
@@ -50,13 +18,13 @@ pub struct Expr {
 pub enum ExprKind {
 	Literal(Value),
 	Ident(Symbol),
+	Var(Symbol),
+	Global(Symbol),
 
 	UnaryOp(UnaryOp, Box<Expr>),
 	BinaryOp(BinaryOp, Box<Expr>, Box<Expr>),
 
 	Assign(Option<BinaryOp>, Box<LValue>, Box<Expr>),
-	AssignVar(Symbol, Option<Box<Expr>>),
-	AssignGlobal(Symbol, Option<Box<Expr>>),
 	FnDef(Option<Symbol>, Vec<Symbol>, Box<Expr>),
 
 	Index(Box<Expr>, Box<Expr>),
@@ -119,7 +87,10 @@ pub struct LValue {
 #[derive(Debug)]
 pub enum LValueKind {
 	Ident(Symbol),
+	Var(Symbol),
+	Global(Symbol),
 	Index(Box<Expr>, Box<Expr>),
+	List(Vec<LValue>, Option<usize>),
 }
 
 impl LValueKind {
@@ -128,17 +99,6 @@ impl LValueKind {
 	}
 }
 
-impl LValue {
-	pub fn from_expr(e: Expr) -> Option<LValue> {
-		let Expr { span, kind } = e;
-		match kind {
-			ExprKind::Ident(i) => Some(LValueKind::Ident(i).span(span)),
-			ExprKind::Index(l, r) => Some(LValueKind::Index(l, r).span(span)),
-			_ => None,
-		}
-	}
-}
-
 impl CatchBlock {
 	pub fn write_to(&self, w: &mut impl fmt::Write, depth: usize) -> fmt::Result {
 		write!(w, "{0: >1$}catch", "", depth * 2)?;
@@ -168,11 +128,23 @@ impl LValue {
 		let depth = depth + 1;
 		match &self.kind {
 			LValueKind::Ident(n) => writeln!(w, "${}", n.name()),
+			LValueKind::Var(n) => writeln!(w, "var ${}", n.name()),
+			LValueKind::Global(n) => writeln!(w, "global ${}", n.name()),
 			LValueKind::Index(l, r) => {
 				writeln!(w, "index")?;
 				l.write_to(w, depth)?;
 				r.write_to(w, depth)
 			}
+			LValueKind::List(ls, i) => {
+				match i {
+					Some(n) => writeln!(w, "list ..#{n}")?,
+					None => writeln!(w, "list")?,
+				}
+				for item in ls {
+					item.write_to(w, depth)?;
+				}
+				Ok(())
+			}
 		}
 	}
 }
@@ -190,38 +162,26 @@ impl Expr {
 		match &self.kind {
 			ExprKind::Literal(val) => writeln!(w, "{val}"),
 			ExprKind::Ident(n) => writeln!(w, "${}", n.name()),
+			ExprKind::Var(n) => writeln!(w, "var ${}", n.name()),
+			ExprKind::Global(n) => writeln!(w, "global ${}", n.name()),
 			ExprKind::UnaryOp(op, e) => {
-				writeln!(w, "uop {op:?}")?;
+				writeln!(w, "uop {op}")?;
 				e.write_to(w, depth)
 			}
 			ExprKind::BinaryOp(op, l, r) => {
-				writeln!(w, "bop {op:?}")?;
+				writeln!(w, "bop {op}")?;
 				l.write_to(w, depth)?;
 				r.write_to(w, depth)
 			}
 			ExprKind::Assign(op, l, r) => {
 				if let Some(op) = op {
-					writeln!(w, "asgn {op:?}")?;
+					writeln!(w, "asgn {op}")?;
 				} else {
 					writeln!(w, "asgn =")?;
 				}
 				l.write_to(w, depth)?;
 				r.write_to(w, depth)
 			}
-			ExprKind::AssignVar(l, r) => {
-				writeln!(w, "var {}", l.name())?;
-				if let Some(r) = r {
-					r.write_to(w, depth)?;
-				}
-				Ok(())
-			}
-			ExprKind::AssignGlobal(l, r) => {
-				writeln!(w, "global {}", l.name())?;
-				if let Some(r) = r {
-					r.write_to(w, depth)?;
-				}
-				Ok(())
-			}
 			ExprKind::FnDef(n, p, b) => {
 				if let Some(n) = n {
 					write!(w, "fndef ${}", n.name())?;

talc-lang/src/parser/parser.rs

@@ -1,13 +1,14 @@
 use std::iter::Peekable;
 
 use crate::{
+	ops::{BinaryOp, UnaryOp},
 	parser::ast::TableItem,
 	symbol::{Symbol, SYM_DOLLAR_SIGN},
 	value::Value,
 };
 
 use super::{
-	ast::{BinaryOp, CatchBlock, Expr, ExprKind, LValue, ListItem, UnaryOp},
+	ast::{CatchBlock, Expr, ExprKind, LValue, LValueKind, ListItem},
 	parse_float, parse_int_literal, parse_str_escapes, Lexer, ParserError, Span,
 	SpanParserError, Token, TokenKind,
 };
@@ -186,6 +187,37 @@ impl TokenKind {
 	}
 }
 
+impl LValue {
+	pub fn from_expr(e: Expr) -> Result<LValue> {
+		let Expr { span, kind } = e;
+		match kind {
+			ExprKind::Ident(i) => Ok(LValueKind::Ident(i).span(span)),
+			ExprKind::Var(i) => Ok(LValueKind::Var(i).span(span)),
+			ExprKind::Global(i) => Ok(LValueKind::Global(i).span(span)),
+			ExprKind::Index(l, r) => Ok(LValueKind::Index(l, r).span(span)),
+			ExprKind::List(items) => {
+				let mut lvals = Vec::new();
+				let mut interp = None;
+				for (i, item) in items.into_iter().enumerate() {
+					match item {
+						ListItem::Item(expr) => lvals.push(LValue::from_expr(*expr)?),
+						ListItem::Interpolate(expr) if interp.is_some() => throw!(
+							expr.span,
+							"list destructure with multiple interpolations"
+						),
+						ListItem::Interpolate(expr) => {
+							interp = Some(i);
+							lvals.push(LValue::from_expr(*expr)?);
+						}
+					}
+				}
+				Ok(LValueKind::List(lvals, interp).span(span))
+			}
+			_ => throw!(span, "invalid lvalue for assignment"),
+		}
+	}
+}
+
 struct Parser<'s> {
 	lexer: Peekable<Lexer<'s>>,
 }
@@ -448,10 +480,20 @@ impl<'s> Parser<'s> {
 	}
 
 	fn parse_term(&mut self) -> Result<Expr> {
-		if let Some(tok) = try_next!(self, T::Identifier) {
+		let Some(tok) = try_next!(self, T::Identifier | T::Var | T::Global) else {
-			Ok(E::Ident(Symbol::get(tok.content)).span(tok.span))
+			return self.parse_term_not_ident()
-		} else {
+		};
-			self.parse_term_not_ident()
+		match tok.kind {
+			T::Identifier => Ok(E::Ident(Symbol::get(tok.content)).span(tok.span)),
+			T::Global => {
+				let ident = expect!(self, T::Identifier);
+				Ok(E::Global(Symbol::get(ident.content)).span(tok.span + ident.span))
+			}
+			T::Var => {
+				let ident = expect!(self, T::Identifier);
+				Ok(E::Var(Symbol::get(ident.content)).span(tok.span + ident.span))
+			}
+			_ => unreachable!("guarenteed by try_next"),
 		}
 	}
 
@@ -601,9 +643,7 @@ impl<'s> Parser<'s> {
 		let lhs = self.parse_pipeline()?;
 		let lhs_span = lhs.span;
 		if let Some(op) = self.peek()?.kind.assign_op() {
-			let Some(lval) = LValue::from_expr(lhs) else {
+			let lval = LValue::from_expr(lhs)?;
-				throw!(lhs_span, "invalid lvalue for assignment")
-			};
 			self.next()?;
 			let rhs = self.parse_decl()?;
 			let rhs_span = rhs.span;
@@ -613,23 +653,6 @@ impl<'s> Parser<'s> {
 		}
 	}
 
-	fn parse_var_decl(&mut self) -> Result<Expr> {
-		let first = expect!(self, T::Var | T::Global);
-		let kind = if first.kind == T::Global {
-			E::AssignGlobal
-		} else {
-			E::AssignVar
-		};
-		let name = expect!(self, T::Identifier);
-		if try_next!(self, T::Equal).is_some() {
-			let val = self.parse_decl()?;
-			let val_span = val.span;
-			Ok(kind(Symbol::get(name.content), Some(b(val))).span(first.span + val_span))
-		} else {
-			Ok(kind(Symbol::get(name.content), None).span(first.span + name.span))
-		}
-	}
-
 	fn parse_fn_decl(&mut self) -> Result<Expr> {
 		let tok_fn = expect!(self, T::Fn);
 		let name = try_next!(self, T::Identifier).map(|t| Symbol::get(t.content));
@@ -653,7 +676,6 @@ impl<'s> Parser<'s> {
 
 	fn parse_decl(&mut self) -> Result<Expr> {
 		match self.peek()?.kind {
-			T::Var | T::Global => self.parse_var_decl(),
 			T::Fn => self.parse_fn_decl(),
 			_ => self.parse_assign(),
 		}

talc-lang/src/parser/util.rs

@@ -1,7 +1,12 @@
 use core::fmt;
-use std::num::{ParseFloatError, ParseIntError};
+use std::num::ParseFloatError;
 
-use crate::lstring::{LStr, LString};
+use num::{bigint::ParseBigIntError, Num};
+
+use crate::{
+	lstring::{LStr, LString},
+	number::Int,
+};
 
 use super::Span;
 
@@ -136,17 +141,17 @@ pub fn parse_float<'a, S: Into<&'a LStr>>(f: S) -> Result<f64, ParseFloatError>
 	s.parse()
 }
 
-pub fn parse_int<'a, S: Into<&'a LStr>>(f: S, radix: u32) -> Result<i64, ParseIntError> {
+pub fn parse_int<'a, S: Into<&'a LStr>>(f: S, radix: u32) -> Result<Int, ParseBigIntError> {
 	let mut s = String::new();
 	for c in f.into().chars() {
 		if c != '_' {
 			s.push(c);
 		}
 	}
-	i64::from_str_radix(&s, radix)
+	Int::from_str_radix(&s, radix)
 }
 
-pub fn parse_int_literal<'a, S: Into<&'a LStr>>(f: S) -> Result<i64, ParseIntError> {
+pub fn parse_int_literal<'a, S: Into<&'a LStr>>(f: S) -> Result<Int, ParseBigIntError> {
 	let f = f.into();
 	match f.chars().nth(1) {
 		Some('x') => parse_int(&f[2..], 16),
@@ -156,33 +161,3 @@ pub fn parse_int_literal<'a, S: Into<&'a LStr>>(f: S) -> Result<i64, ParseIntErr
 		_ => parse_int(f, 10),
 	}
 }
-
-pub fn to_lstring_radix(n: i64, radix: u32, upper: bool) -> LString {
-	let mut result = vec![];
-	let mut begin = 0;
-
-	let mut x;
-	if n < 0 {
-		result.push('-' as u32 as u8);
-		begin = 1;
-		x = (-n) as u64;
-	} else {
-		x = n as u64;
-	}
-
-	loop {
-		let m = x % (radix as u64);
-		x /= radix as u64;
-
-		let mut c = char::from_digit(m as u32, radix).unwrap();
-		if upper {
-			c.make_ascii_uppercase();
-		}
-		result.push(c as u8);
-		if x == 0 {
-			break
-		}
-	}
-	result[begin..].reverse();
-	LString::from(result)
-}

talc-lang/src/value/mod.rs

@@ -96,6 +96,15 @@ impl Value {
 		recur: &mut Vec<*const ()>,
 	) -> io::Result<()> {
 		use std::io::Write;
+
+		fn write_float(w: &mut LString, f: f64) -> io::Result<()> {
+			write!(w, "{f:.}")?;
+			if f.fract() == 0.0 {
+				write!(w, ".0")?;
+			}
+			Ok(())
+		}
+
 		match self {
 			Self::Nil => write!(w, "nil"),
 			Self::Bool(b) => write!(w, "{b}"),
@@ -105,20 +114,24 @@ impl Value {
 				if name.is_identifier() {
 					w.extend(name.as_bytes());
 				} else {
-					write!(w, "{name:?}")?;
+					write!(w, "{}", name.to_escaped())?;
 				}
 				Ok(())
 			}
 			Self::Range(r) => write!(w, "{r}"),
 			Self::Int(i) => write!(w, "{i}"),
-			Self::Float(x) => write!(w, "{x:?}"),
+			Self::Float(x) => write_float(w, *x),
 			Self::Ratio(r) => write!(w, "{}/{}", r.numer(), r.denom()),
 			Self::Complex(z) => {
-				write!(w, "{:?}", z.re())?;
+				write_float(w, z.re())?;
-				if z.im() >= 0.0 || z.im.is_nan() {
+				if z.im().signum() > 0.0 || z.im.is_nan() {
-					w.push_byte(b'+');
+					w.push_bytes(b" + ");
+				} else {
+					w.push_bytes(b" - ");
 				}
-				write!(w, "{:?}i", z.im())
+				write_float(w, z.im().abs())?;
+				w.push_byte(b'i');
+				Ok(())
 			}
 			Self::Cell(v) if repr => {
 				if recur.contains(&(v.as_ptr() as _)) {
@@ -139,7 +152,7 @@ impl Value {
 				recur.pop();
 				Ok(())
 			}
-			Self::String(s) if repr => write!(w, "{s:?}"),
+			Self::String(s) if repr => write!(w, "{}", s.to_escaped()),
 			Self::String(s) => w.write_all(s.as_bytes()),
 
 			Self::List(l) => {

talc-lang/src/vm.rs

@@ -10,9 +10,10 @@ use crate::{
 	chunk::Instruction,
 	exception::{throw, Exception, Result},
 	lstring::{LStr, LString},
-	parser::ast::{BinaryOp, UnaryOp},
+	ops::{BinaryOp, UnaryOp},
 	symbol::{
 		Symbol, SYM_CALL_STACK_OVERFLOW, SYM_INTERRUPTED, SYM_NAME_ERROR, SYM_TYPE_ERROR,
+		SYM_VALUE_ERROR,
 	},
 	value::{
 		function::{FuncAttrs, Function, NativeFunc},
@@ -486,20 +487,57 @@ impl Vm {
 				drop(table_ref);
 				self.push(Value::Table(table));
 			}
+			I::ListDestructure(l, r, interp) => {
+				let lst = self.pop();
+				let Value::List(lst) = lst else {
+					throw!(*SYM_TYPE_ERROR, "cannot destructure {lst:#} into list")
+				};
+				let lst_ref = lst.borrow();
+				let lst_len = lst_ref.len();
+
+				let (l, r) = (l as usize, r as usize);
+
+				if lst_len < l + r || (lst_len != l + r && !interp) {
+					throw!(*SYM_VALUE_ERROR, "wrong number of items to destructure");
+				}
+
+				for i in ((lst_len - r)..lst_len).rev() {
+					self.push(lst_ref[i].clone());
+				}
+
+				if interp {
+					let slice = &lst_ref[l..(lst_len - r)];
+					self.push(Value::from(slice.to_vec()));
+				}
+
+				for i in (0..l).rev() {
+					self.push(lst_ref[i].clone());
+				}
+			}
 			// [ct, idx] -> [ct[idx]]
 			I::Index => {
 				let idx = self.pop();
 				let ct = self.pop();
 				self.push(ct.index(idx)?);
 			}
-			// [ct, idx, v] -> [v], ct[idx] = v
+			// [v, ct, idx] -> [v], ct[idx] = v
 			I::StoreIndex => {
-				let v = self.pop();
 				let idx = self.pop();
 				let ct = self.pop();
+				let v = self.pop();
 				ct.store_index(self, idx, v.clone())?;
 				self.push(v);
 			}
+			// [v, ct, idx] -> [ct[idx] op v], ct[idx] op= v
+			I::StoreIndexOp(op) => {
+				let idx = self.pop();
+				let ct = self.pop();
+				let v = self.pop();
+				let w = ct.index(idx.clone())?;
+				let o = binary_op(op, w, v)?;
+				ct.store_index(self, idx, o.clone())?;
+				self.push(o);
+			}
 			// ip = n
 			I::Jump(n) => {
 				self.check_interrupt()?;

talc-std/src/format.rs

@@ -104,14 +104,14 @@ impl<'p> FmtParser<'p> {
 		let Ok(i) = parse_int(s, 10) else {
 			throw!(*SYM_FORMAT_ERROR, "code {{{}}}: invalid integer", self.code)
 		};
-		if i < 0 {
+		let Some(n) = i.to_usize() else {
 			throw!(
 				*SYM_FORMAT_ERROR,
 				"code {{{}}}: integer may not be negative",
 				self.code
 			)
-		}
+		};
-		Ok(Some(i as usize))
+		Ok(Some(n))
 	}
 
 	fn next_fmt_index(&mut self) -> Result<Option<FmtIndex>> {
@@ -351,7 +351,7 @@ fn format_string(
 			buf.push_lstr(s);
 			Ok(())
 		}
-		FmtType::Repr => write!(buf, "{:?}", s),
+		FmtType::Repr => write!(buf, "{}", s.to_escaped()),
 		_ => throw!(*SYM_FORMAT_ERROR, "invalid format specifier for string"),
 	};
 	res.map_err(|e| exception!(*SYM_FORMAT_ERROR, "{e}"))

talc-std/src/value.rs

@@ -92,11 +92,11 @@ pub fn as_(_: &mut Vm, args: Vec<Value>) -> Result<Value> {
 		(Value::Float(x), b"complex") => Ok(Value::Complex(x.into())),
 
 		(Value::String(s), b"int") => parse_int(s.as_ref(), 10)
-			.map(i64::into)
+			.map(Value::from)
 			.map_err(|_| exception!(*SYM_VALUE_ERROR, "could not parse {s:#} as integer")),
 
 		(Value::String(s), b"float") => parse_float(s.as_ref())
-			.map(f64::into)
+			.map(Value::from)
 			.map_err(|_| exception!(*SYM_VALUE_ERROR, "could not parse {s:#} as float")),
 
 		(v, _) => throw!(