diff --git a/Cargo.lock b/Cargo.lock
index 637c51f..0250c84 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -55,9 +55,9 @@ checksum = "613afe47fcd5fac7ccf1db93babcb082c5994d996f20b8b159f2ad1658eb5724"
 
 [[package]]
 name = "clap"
-version = "4.5.20"
+version = "4.5.21"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b97f376d85a664d5837dbae44bf546e6477a679ff6610010f17276f686d867e8"
+checksum = "fb3b4b9e5a7c7514dfa52869339ee98b3156b0bfb4e8a77c4ff4babb64b1604f"
 dependencies = [
  "clap_builder",
  "clap_derive",
@@ -65,9 +65,9 @@ dependencies = [
 
 [[package]]
 name = "clap_builder"
-version = "4.5.20"
+version = "4.5.21"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "19bc80abd44e4bed93ca373a0704ccbd1b710dc5749406201bb018272808dc54"
+checksum = "b17a95aa67cc7b5ebd32aa5370189aa0d79069ef1c64ce893bd30fb24bff20ec"
 dependencies = [
  "anstyle",
  "clap_lex",
@@ -87,9 +87,9 @@ dependencies = [
 
 [[package]]
 name = "clap_lex"
-version = "0.7.2"
+version = "0.7.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1462739cb27611015575c0c11df5df7601141071f07518d56fcc1be504cbec97"
+checksum = "afb84c814227b90d6895e01398aee0d8033c00e7466aca416fb6a8e0eb19d8a7"
 
 [[package]]
 name = "clipboard-win"
diff --git a/Cargo.toml b/Cargo.toml
index 01d4c64..dbc4fa2 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -2,8 +2,6 @@
 members = ["talc-lang", "talc-bin", "talc-std", "talc-macros"]
 resolver = "2"
 
-[profile.release]
-
 [profile.release-opt]
 inherits = "release"
 lto = "fat"
diff --git a/README.md b/README.md
index ae5dd08..4dfec79 100644
--- a/README.md
+++ b/README.md
@@ -3,5 +3,5 @@
 ## installation
 
 ```sh
-cargo install --profile release-lto --path talc-bin
+cargo install --profile release-opt --path talc-bin
 ```
diff --git a/talc-bin/src/helper.rs b/talc-bin/src/helper.rs
index 3c4a56b..07f811d 100644
--- a/talc-bin/src/helper.rs
+++ b/talc-bin/src/helper.rs
@@ -10,7 +10,7 @@ use rustyline::{
 use talc_lang::{
 	lstring::LStr,
 	parser::{Lexer, Pos, Span, TokenKind},
-	Vm,
+	vm::Vm,
 };
 
 pub struct TalcHelper {
diff --git a/talc-bin/src/main.rs b/talc-bin/src/main.rs
index 53e0b1f..7b34596 100644
--- a/talc-bin/src/main.rs
+++ b/talc-bin/src/main.rs
@@ -3,10 +3,11 @@ use std::{path::PathBuf, process::ExitCode, rc::Rc};
 use talc_lang::{
 	compiler::compile,
 	lstring::LString,
-	optimize, parser, serial,
+	optimize::optimize,
+	parser, serial,
 	symbol::Symbol,
 	value::{function::disasm_recursive, Value},
-	Vm,
+	vm::Vm,
 };
 
 mod helper;
diff --git a/talc-bin/src/repl.rs b/talc-bin/src/repl.rs
index 07d3f86..e974d2d 100644
--- a/talc-bin/src/repl.rs
+++ b/talc-bin/src/repl.rs
@@ -8,10 +8,12 @@ use rustyline::{
 };
 use talc_lang::{
 	compiler::compile_repl,
-	lstr, optimize, parser,
+	lstr,
+	optimize::optimize,
+	parser,
 	symbol::{symbol, Symbol},
 	value::{function::disasm_recursive, Value},
-	Vm,
+	vm::Vm,
 };
 
 use crate::{helper::TalcHelper, Args};
@@ -117,17 +119,14 @@ fn exec_line(
 		eprintln!("{}", ex);
 	}
 
-	let (f, g) = match compile_repl(&ex, globals) {
-		Ok(pair) => pair,
+	let func = match compile_repl(&ex, globals) {
+		Ok(f) => Rc::new(f),
 		Err(e) => {
 			eprintln!("{}Error:{} {e}", c.error, c.reset);
 			return
 		}
 	};
 
-	*globals = g;
-	let func = Rc::new(f);
-
 	if args.disasm {
 		if let Err(e) = disasm_recursive(&func, &mut std::io::stderr()) {
 			eprintln!("{}Error:{} {e}", c.error, c.reset);
diff --git a/talc-lang/Cargo.toml b/talc-lang/Cargo.toml
index ec41ef7..2ddd4c8 100644
--- a/talc-lang/Cargo.toml
+++ b/talc-lang/Cargo.toml
@@ -9,5 +9,3 @@ num-rational = { version = "0.4", default-features = false, features = [] }
 num-traits = "0.2"
 lazy_static = "1.5"
 unicode-ident = "1.0"
-
-[build-dependencies]
diff --git a/talc-lang/src/compiler.rs b/talc-lang/src/compiler.rs
index 873be72..a2516e3 100644
--- a/talc-lang/src/compiler.rs
+++ b/talc-lang/src/compiler.rs
@@ -5,7 +5,7 @@ use std::rc::Rc;
 use crate::chunk::{Arg24, Catch, Chunk, Instruction as I};
 use crate::parser::ast::{BinaryOp, CatchBlock, Expr, ExprKind, LValue, LValueKind};
 use crate::parser::Pos;
-use crate::symbol::{Symbol, SYM_SELF};
+use crate::symbol::{Symbol, SYM_REPL, SYM_SELF};
 use crate::throw;
 use crate::value::function::{FuncAttrs, Function};
 use crate::value::Value;
@@ -39,18 +39,12 @@ enum ResolveOutcome {
 }
 
 #[derive(Clone, Copy, Debug, PartialEq, Eq)]
-pub enum VarKind {
+enum VarKind {
 	Local(usize),
 	Closed(usize),
 	Global,
 }
 
-#[derive(Debug, Clone)]
-pub struct Var {
-	name: Symbol,
-	kind: VarKind,
-}
-
 #[derive(Clone, Copy, PartialEq, Eq)]
 enum CompilerMode {
 	Function,
@@ -72,8 +66,8 @@ struct Compiler<'a> {
 	chunk: Chunk,
 	attrs: FuncAttrs,
 	// variables
-	scope: HashMap<Symbol, Var>,
-	shadowed: Vec<(Symbol, Option<Var>)>,
+	scope: HashMap<Symbol, VarKind>,
+	shadowed: Vec<(Symbol, Option<VarKind>)>,
 	closes: Vec<(Symbol, usize)>,
 	local_count: usize,
 	// break and continue
@@ -87,22 +81,16 @@ pub fn compile(expr: &Expr, name: Option<Symbol>) -> Result<Function> {
 	Ok(comp.finish())
 }
 
-pub fn compile_repl(expr: &Expr, globals: &[Symbol]) -> Result<(Function, Vec<Symbol>)> {
+pub fn compile_repl(expr: &Expr, globals: &mut Vec<Symbol>) -> Result<Function> {
 	let mut comp = Compiler::new_repl(globals);
 	comp.expr(expr)?;
-	Ok(comp.finish_repl())
+	Ok(comp.finish_repl(globals))
 }
 
 impl<'a> Default for Compiler<'a> {
 	fn default() -> Self {
 		let mut scope = HashMap::new();
-		scope.insert(
-			*SYM_SELF,
-			Var {
-				name: *SYM_SELF,
-				kind: VarKind::Local(0),
-			},
-		);
+		scope.insert(*SYM_SELF, VarKind::Local(0));
 		Self {
 			mode: CompilerMode::Function,
 			parent: None,
@@ -124,7 +112,7 @@ impl<'a> Compiler<'a> {
 			mode: CompilerMode::Repl,
 			attrs: FuncAttrs {
 				arity: 0,
-				name: Some(Symbol::get("<repl>")),
+				name: Some(*SYM_REPL),
 			},
 			..Self::default()
 		};
@@ -162,30 +150,29 @@ impl<'a> Compiler<'a> {
 		new
 	}
 
-	pub fn finish(mut self) -> Function {
+	fn finish(mut self) -> Function {
 		self.emit(I::Return);
 		Function::new(Rc::new(self.chunk), self.attrs, self.closes.len())
 	}
 
-	pub fn finish_inner(mut self) -> (Function, Vec<(Symbol, usize)>) {
+	fn finish_inner(mut self) -> (Function, Vec<(Symbol, usize)>) {
 		self.emit(I::Return);
-		// TODO closure
 		(
 			Function::new(Rc::new(self.chunk), self.attrs, self.closes.len()),
 			self.closes,
 		)
 	}
 
-	pub fn finish_repl(mut self) -> (Function, Vec<Symbol>) {
+	fn finish_repl(mut self, globals: &mut Vec<Symbol>) -> Function {
 		self.emit(I::Return);
-		(
-			// TODO closure
-			Function::new(Rc::new(self.chunk), self.attrs, self.closes.len()),
-			self.scope
-				.into_iter()
-				.filter_map(|(_, v)| (v.kind == VarKind::Global).then_some(v.name))
-				.collect(),
-		)
+
+		globals.clear();
+		for (name, kind) in self.scope.iter() {
+			if *kind == VarKind::Global {
+				globals.push(*name);
+			}
+		}
+		Function::new(Rc::new(self.chunk), self.attrs, self.closes.len())
 	}
 
 	//
@@ -306,7 +293,7 @@ impl<'a> Compiler<'a> {
 			let (name, var) = self.shadowed.pop().expect("scope bad");
 
 			if let Some(in_var) = self.scope.get(&name) {
-				if in_var.kind != VarKind::Global {
+				if *in_var != VarKind::Global {
 					locals += 1;
 				}
 			}
@@ -329,8 +316,8 @@ impl<'a> Compiler<'a> {
 	//
 
 	fn resolve_name(&self, name: Symbol) -> ResolveOutcome {
-		if let Some(v) = self.scope.get(&name) {
-			return ResolveOutcome::Var(v.kind)
+		if let Some(kind) = self.scope.get(&name) {
+			return ResolveOutcome::Var(*kind)
 		}
 		let Some(parent) = self.parent else {
 			return ResolveOutcome::None
@@ -369,10 +356,7 @@ impl<'a> Compiler<'a> {
 	}
 
 	fn declare_local(&mut self, name: Symbol) -> usize {
-		let local = Var {
-			name,
-			kind: VarKind::Local(self.local_count),
-		};
+		let local = VarKind::Local(self.local_count);
 		self.local_count += 1;
 		let shadowed = self.scope.insert(name, local);
 		self.shadowed.push((name, shadowed));
@@ -391,11 +375,7 @@ impl<'a> Compiler<'a> {
 	}
 
 	fn declare_global(&mut self, name: Symbol) {
-		let global = Var {
-			name,
-			kind: VarKind::Global,
-		};
-		let shadowed = self.scope.insert(name, global);
+		let shadowed = self.scope.insert(name, VarKind::Global);
 		self.shadowed.push((name, shadowed));
 	}
 
@@ -752,9 +732,7 @@ impl<'a> Compiler<'a> {
 			match self.resolve_name(name) {
 				ResolveOutcome::Var(VarKind::Local(n)) => {
 					self.emit(I::CloseOver(Arg24::from_usize(n)));
-					self.scope.entry(name).and_modify(|v| {
-						v.kind = VarKind::Closed(n);
-					});
+					self.scope.insert(name, VarKind::Closed(n));
 				}
 				ResolveOutcome::Var(VarKind::Closed(n)) => {
 					self.emit(I::LoadLocal(Arg24::from_usize(n)));
diff --git a/talc-lang/src/lib.rs b/talc-lang/src/lib.rs
index ff3a7e9..0d044f6 100644
--- a/talc-lang/src/lib.rs
+++ b/talc-lang/src/lib.rs
@@ -8,12 +8,9 @@ pub mod chunk;
 pub mod compiler;
 pub mod exception;
 pub mod lstring;
-mod optimize;
-pub use optimize::optimize;
+pub mod optimize;
 pub mod parser;
 pub mod serial;
 pub mod symbol;
 pub mod value;
-
-mod vm;
-pub use vm::Vm;
+pub mod vm;
diff --git a/talc-lang/src/optimize.rs b/talc-lang/src/optimize.rs
index a43d2bb..1097d49 100644
--- a/talc-lang/src/optimize.rs
+++ b/talc-lang/src/optimize.rs
@@ -27,12 +27,12 @@ struct OptState {
 
 impl OptState {
 	#[inline]
-	pub const fn empty() -> Self {
+	const fn empty() -> Self {
 		Self { ret: false }
 	}
 
 	#[inline]
-	pub const fn ret(ret: bool) -> Self {
+	const fn ret(ret: bool) -> Self {
 		Self { ret }
 	}
 }
@@ -214,7 +214,7 @@ fn optimize_ex_with(expr: &mut Expr, state: OptState) {
 	}
 }
 
-pub fn optimize_lv(e: &mut LValue) {
+fn optimize_lv(e: &mut LValue) {
 	match &mut e.kind {
 		LValueKind::Ident(_) => (),
 		LValueKind::Index(l, r) => {
@@ -224,6 +224,6 @@ pub fn optimize_lv(e: &mut LValue) {
 	}
 }
 
-pub fn optimize_cb(e: &mut CatchBlock) {
+fn optimize_cb(e: &mut CatchBlock) {
 	optimize_ex(&mut e.body);
 }
diff --git a/talc-lang/src/parser/ast.rs b/talc-lang/src/parser/ast.rs
index 1ea684f..f25ce49 100644
--- a/talc-lang/src/parser/ast.rs
+++ b/talc-lang/src/parser/ast.rs
@@ -34,6 +34,7 @@ pub enum BinaryOp {
 pub enum UnaryOp {
 	Neg,
 	Not,
+	BitNot,
 	RangeEndless,
 }
 
diff --git a/talc-lang/src/parser/lexer.rs b/talc-lang/src/parser/lexer.rs
index ecc178b..a85578d 100644
--- a/talc-lang/src/parser/lexer.rs
+++ b/talc-lang/src/parser/lexer.rs
@@ -11,7 +11,7 @@ pub enum TokenKind {
 	Eof,
 	LineSeparator,
 
-	Bang,
+	Tilde,
 	BangEqual,
 	HashAmper,
 	HashAmperEqual,
@@ -42,7 +42,6 @@ pub enum TokenKind {
 	SlashSlash,
 	SlashSlashEqual,
 	SlashEqual,
-	Colon,
 	Less,
 	LessLess,
 	LessLessEqual,
@@ -101,7 +100,7 @@ impl TokenKind {
 		match self {
 			K::Eof => "end of file",
 			K::LineSeparator => "line separator",
-			K::Bang => "'!'",
+			K::Tilde => "'~'",
 			K::BangEqual => "'!='",
 			K::HashAmper => "'#&'",
 			K::HashAmperEqual => "'#&='",
@@ -123,7 +122,7 @@ impl TokenKind {
 			K::Comma => "','",
 			K::Minus => "'-'",
 			K::MinusEqual => "'-='",
-			K::Arrow => "'=>'",
+			K::Arrow => "'->'",
 			K::Dot => "'.'",
 			K::DotDot => "'..'",
 			K::DotDotStar => "'..*'",
@@ -132,7 +131,6 @@ impl TokenKind {
 			K::SlashSlash => "'//'",
 			K::SlashSlashEqual => "'//='",
 			K::SlashEqual => "'/='",
-			K::Colon => "':'",
 			K::Less => "'<'",
 			K::LessLess => "'<<'",
 			K::LessLessEqual => "'<<='",
@@ -526,11 +524,12 @@ impl<'s> Lexer<'s> {
 				'!' => self.line_comment(),
 				_ => self.unexpected(),
 			},
-			// lists
+			'~' => self.and_emit(K::Tilde),
 			'!' => match self.and_peek()? {
 				'=' => self.and_emit(K::BangEqual),
-				_ => self.emit(K::Bang),
+				_ => self.unexpected(),
 			},
+			// lists
 			'&' => match self.and_peek()? {
 				'=' => self.and_emit(K::AmperEqual),
 				_ => self.emit(K::Amper),
@@ -569,7 +568,7 @@ impl<'s> Lexer<'s> {
 				c if is_xid_start(c) || c == '_' || c == '"' || c == '\'' => {
 					self.next_symbol()
 				}
-				_ => self.emit(K::Colon),
+				_ => self.unexpected(),
 			},
 			'0'..='9' => self.next_number(),
 			c if c == '_' || is_xid_start(c) => self.next_ident(),
diff --git a/talc-lang/src/parser/parser.rs b/talc-lang/src/parser/parser.rs
index fc89322..708ac81 100644
--- a/talc-lang/src/parser/parser.rs
+++ b/talc-lang/src/parser/parser.rs
@@ -54,7 +54,7 @@ macro_rules! throw {
 }
 
 impl TokenKind {
-	pub fn assign_op(self) -> Option<Option<BinaryOp>> {
+	fn assign_op(self) -> Option<Option<BinaryOp>> {
 		Some(match self {
 			T::PlusPlusEqual => Some(BinaryOp::Concat),
 			T::AmperEqual => Some(BinaryOp::Append),
@@ -75,7 +75,7 @@ impl TokenKind {
 		})
 	}
 
-	pub fn binary_op(self) -> Option<BinaryOp> {
+	fn binary_op(self) -> Option<BinaryOp> {
 		Some(match self {
 			T::EqualEqual => BinaryOp::Eq,
 			T::BangEqual => BinaryOp::Ne,
@@ -103,15 +103,16 @@ impl TokenKind {
 		})
 	}
 
-	pub fn unary_op(self) -> Option<UnaryOp> {
+	fn unary_op(self) -> Option<UnaryOp> {
 		match self {
 			T::Minus => Some(UnaryOp::Neg),
 			T::Not => Some(UnaryOp::Not),
+			T::Tilde => Some(UnaryOp::BitNot),
 			_ => None,
 		}
 	}
 
-	pub fn postfix_unary_op(self) -> Option<UnaryOp> {
+	fn postfix_unary_op(self) -> Option<UnaryOp> {
 		match self {
 			T::DotDotStar => Some(UnaryOp::RangeEndless),
 			_ => None,
@@ -120,17 +121,17 @@ impl TokenKind {
 }
 
 impl UnaryOp {
-	pub fn precedence(self) -> u8 {
+	fn precedence(self) -> u8 {
 		match self {
 			UnaryOp::Not => 0,
 			UnaryOp::RangeEndless => 40,
-			UnaryOp::Neg => 110,
+			UnaryOp::Neg | UnaryOp::BitNot => 110,
 		}
 	}
 }
 
 impl BinaryOp {
-	pub fn precedence(self) -> (u8, u8) {
+	fn precedence(self) -> (u8, u8) {
 		match self {
 			BinaryOp::Eq
 			| BinaryOp::Ne
@@ -166,8 +167,8 @@ impl TokenKind {
 				| T::Break | T::Var
 				| T::Global | T::Fn
 				| T::Not | T::Backslash
-				| T::Colon | T::Minus
-				| T::Identifier
+				| T::Amper | T::Minus
+				| T::Tilde | T::Identifier
 				| T::LParen | T::LBrack
 				| T::LBrace | T::Dollar
 				| T::Do | T::If
@@ -494,7 +495,7 @@ impl<'s> Parser<'s> {
 	}
 
 	fn parse_lambda(&mut self) -> Result<Expr> {
-		let tok = try_next!(self, T::Backslash | T::Colon);
+		let tok = try_next!(self, T::Backslash | T::Amper);
 		match tok {
 			Some(Token {
 				kind: T::Backslash,
@@ -502,13 +503,13 @@ impl<'s> Parser<'s> {
 				..
 			}) => {
 				let args = self.parse_ident_list()?;
-				expect!(self, T::Arrow);
+				expect!(self, T::Dot);
 				let body = self.parse_lambda()?;
 				let body_span = body.span;
 				Ok(E::Lambda(args, b(body)).span(span + body_span))
 			}
 			Some(Token {
-				kind: T::Colon,
+				kind: T::Amper,
 				span,
 				..
 			}) => {
diff --git a/talc-lang/src/symbol.rs b/talc-lang/src/symbol.rs
index 8fe021e..abb266b 100644
--- a/talc-lang/src/symbol.rs
+++ b/talc-lang/src/symbol.rs
@@ -12,6 +12,7 @@ struct SymbolTable {
 }
 
 lazy_static! {
+	pub static ref SYM_REPL: Symbol = symbol!("<repl>");
 	pub static ref SYM_SELF: Symbol = symbol!(self);
 	pub static ref SYM_DOLLAR_SIGN: Symbol = symbol!("$");
 	pub static ref SYM_NIL: Symbol = symbol!(nil);
diff --git a/talc-lang/src/value/function.rs b/talc-lang/src/value/function.rs
index 2d8c85f..970a941 100644
--- a/talc-lang/src/value/function.rs
+++ b/talc-lang/src/value/function.rs
@@ -1,6 +1,6 @@
 use std::{cell::RefCell, rc::Rc};
 
-use crate::{chunk::Chunk, exception::Result, symbol::Symbol, Vm};
+use crate::{chunk::Chunk, exception::Result, symbol::Symbol, vm::Vm};
 
 use super::{CellValue, Value};
 
diff --git a/talc-lang/src/value/index.rs b/talc-lang/src/value/index.rs
index b0720da..98184ff 100644
--- a/talc-lang/src/value/index.rs
+++ b/talc-lang/src/value/index.rs
@@ -2,7 +2,8 @@ use crate::{
 	exception::{throw, Result},
 	symbol::{symbol, SYM_END_ITERATION, SYM_INDEX_ERROR, SYM_TYPE_ERROR},
 	value::function::NativeFunc,
-	vmcalliter, Vm,
+	vm::Vm,
+	vmcalliter,
 };
 
 use super::{range::RangeType, Value};
@@ -126,7 +127,11 @@ impl Value {
 			(V::Table(t), i) if i.hashable() => {
 				let mut t = t.borrow_mut();
 				let i = i.try_into()?;
-				t.insert(i, val);
+				if val == Value::Nil {
+					t.remove(&i);
+				} else {
+					t.insert(i, val);
+				}
 				Ok(())
 			}
 			(V::List(t), V::Range(r)) => {
diff --git a/talc-lang/src/value/mod.rs b/talc-lang/src/value/mod.rs
index 3821184..33a1b4c 100644
--- a/talc-lang/src/value/mod.rs
+++ b/talc-lang/src/value/mod.rs
@@ -169,6 +169,9 @@ impl Value {
 				if recur.contains(&(t.as_ptr() as _)) {
 					return w.write_all(b"{...}")
 				}
+				if t.borrow().len() == 0 {
+					return w.write_all(b"{}")
+				}
 				w.write_all(b"{ ")?;
 				recur.push(t.as_ptr() as _);
 				for (i, (k, v)) in t.borrow().iter().enumerate() {
@@ -176,7 +179,7 @@ impl Value {
 						w.write_all(b", ")?;
 					}
 					k.0.write_table_key_repr(w, recur)?;
-					w.write_all(b" = ")?;
+					w.write_all(b"=")?;
 					v.write_to_lstring(w, true, recur)?;
 				}
 				recur.pop();
diff --git a/talc-lang/src/value/ops.rs b/talc-lang/src/value/ops.rs
index 05265b4..421eea2 100644
--- a/talc-lang/src/value/ops.rs
+++ b/talc-lang/src/value/ops.rs
@@ -1,7 +1,7 @@
 use std::{
 	cell::RefCell,
 	cmp::Ordering,
-	ops::{Add, BitAnd, BitOr, BitXor, Div, Mul, Neg, Shl, Shr, Sub},
+	ops::{Add, BitAnd, BitOr, BitXor, Div, Mul, Neg, Not, Shl, Shr, Sub},
 	rc::Rc,
 };
 
@@ -14,7 +14,7 @@ use crate::{
 	lstring::LString,
 	symbol::{symbol, SYM_END_ITERATION, SYM_TYPE_ERROR, SYM_VALUE_ERROR},
 	value::range::RangeType,
-	Vm,
+	vm::Vm,
 };
 
 use super::{
@@ -388,7 +388,9 @@ impl Shl<Value> for Value {
 	fn shl(self, rhs: Value) -> Self::Output {
 		use Value as V;
 		match (self, rhs) {
-			(V::Int(a), V::Int(b)) => Ok(Value::Int(((a as u64) << b as u64) as i64)),
+			(V::Int(a), V::Int(b)) => {
+				Ok(Value::Int((a as u64).wrapping_shl(b as u32) as i64))
+			}
 			(l, r) => throw!(*SYM_TYPE_ERROR, "cannot shift {l:#} left by {r:#}"),
 		}
 	}
@@ -400,7 +402,9 @@ impl Shr<Value> for Value {
 	fn shr(self, rhs: Value) -> Self::Output {
 		use Value as V;
 		match (self, rhs) {
-			(V::Int(a), V::Int(b)) => Ok(Value::Int((a as u64 >> b as u64) as i64)),
+			(V::Int(a), V::Int(b)) => {
+				Ok(Value::Int((a as u64).wrapping_shr(b as u32) as i64))
+			}
 			(l, r) => throw!(*SYM_TYPE_ERROR, "cannot shift {l:#} right by {r:#}"),
 		}
 	}
@@ -413,7 +417,7 @@ impl BitAnd<Value> for Value {
 		use Value as V;
 		match (self, rhs) {
 			(V::Int(a), V::Int(b)) => Ok(Value::Int(a & b)),
-			(l, r) => throw!(*SYM_TYPE_ERROR, "cannot shift {l:#} right by {r:#}"),
+			(l, r) => throw!(*SYM_TYPE_ERROR, "cannot bitwise and {l:#} and {r:#}"),
 		}
 	}
 }
@@ -425,7 +429,7 @@ impl BitXor<Value> for Value {
 		use Value as V;
 		match (self, rhs) {
 			(V::Int(a), V::Int(b)) => Ok(Value::Int(a ^ b)),
-			(l, r) => throw!(*SYM_TYPE_ERROR, "cannot shift {l:#} right by {r:#}"),
+			(l, r) => throw!(*SYM_TYPE_ERROR, "cannot bitwise xor {l:#} and {r:#}"),
 		}
 	}
 }
@@ -437,7 +441,19 @@ impl BitOr<Value> for Value {
 		use Value as V;
 		match (self, rhs) {
 			(V::Int(a), V::Int(b)) => Ok(Value::Int(a | b)),
-			(l, r) => throw!(*SYM_TYPE_ERROR, "cannot shift {l:#} right by {r:#}"),
+			(l, r) => throw!(*SYM_TYPE_ERROR, "cannot bitwise or {l:#} and {r:#}"),
+		}
+	}
+}
+
+impl Not for Value {
+	type Output = Result<Value>;
+
+	fn not(self) -> Self::Output {
+		use Value as V;
+		match self {
+			V::Int(a) => Ok(Value::Int(!a)),
+			v => throw!(*SYM_TYPE_ERROR, "cannot bitwise not {v:#}"),
 		}
 	}
 }
diff --git a/talc-lang/src/vm.rs b/talc-lang/src/vm.rs
index a9a6593..5d93251 100644
--- a/talc-lang/src/vm.rs
+++ b/talc-lang/src/vm.rs
@@ -1,6 +1,7 @@
 use std::{
 	cmp::Ordering,
 	collections::HashMap,
+	ops::Not,
 	rc::Rc,
 	sync::{atomic::AtomicBool, Arc},
 };
@@ -84,6 +85,7 @@ pub fn unary_op(o: UnaryOp, a: Value) -> Result<Value> {
 	match o {
 		UnaryOp::Neg => -a,
 		UnaryOp::Not => Ok(Value::Bool(!a.truthy())),
+		UnaryOp::BitNot => a.not(),
 		UnaryOp::RangeEndless => a.range_endless(),
 	}
 }
@@ -243,7 +245,7 @@ impl Vm {
 		res
 	}
 
-	fn check_interrupt(&mut self) -> Result<()> {
+	pub fn check_interrupt(&mut self) -> Result<()> {
 		if self
 			.interrupt
 			.fetch_and(false, std::sync::atomic::Ordering::Relaxed)
@@ -399,7 +401,11 @@ impl Vm {
 				for _ in 0..n {
 					let v = self.pop();
 					let k = self.pop();
-					table.insert(k.try_into()?, v);
+					if v == Value::Nil {
+						table.remove(&k.try_into()?);
+					} else {
+						table.insert(k.try_into()?, v);
+					}
 				}
 				self.push(table.into());
 			}
@@ -415,18 +421,22 @@ impl Vm {
 					// can't panic: pop_n checked that ext would have len 2*n
 					let v = ext.pop().unwrap();
 					let k = ext.pop().unwrap();
-					table_ref.insert(k.try_into()?, v);
+					if v == Value::Nil {
+						table_ref.remove(&k.try_into()?);
+					} else {
+						table_ref.insert(k.try_into()?, v);
+					}
 				}
 				drop(table_ref);
 				self.push(Value::Table(table));
 			}
-			// [ct, idx] -> [ct!idx]
+			// [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
+			// [ct, idx, v] -> [v], ct[idx] = v
 			I::StoreIndex => {
 				let v = self.pop();
 				let idx = self.pop();
diff --git a/talc-lang/tests/vm.rs b/talc-lang/tests/vm.rs
index b5c1283..75f3a27 100644
--- a/talc-lang/tests/vm.rs
+++ b/talc-lang/tests/vm.rs
@@ -1,6 +1,6 @@
 use std::rc::Rc;
 
-use talc_lang::{compiler::compile, optimize, parser, value::Value, Vm};
+use talc_lang::{compiler::compile, optimize::optimize, parser, value::Value, vm::Vm};
 
 fn assert_eval(src: &str, value: Value) {
 	let mut ex = parser::parse(src).expect(&format!("failed to parse expression"));
@@ -88,7 +88,7 @@ fn closures() {
 	assert_eval(
 		"
             var x = 2
-            next = \\-> do x = x * 2 + 1 end
+            next = \\. do x = x * 2 + 1 end
             next() + next() + next()
         ",
 		Value::Int(5 + 11 + 23),
diff --git a/talc-std/Cargo.toml b/talc-std/Cargo.toml
index 881e8a1..bfafd4d 100644
--- a/talc-std/Cargo.toml
+++ b/talc-std/Cargo.toml
@@ -7,9 +7,10 @@ edition = "2021"
 talc-lang = { path = "../talc-lang" }
 talc-macros = { path = "../talc-macros" }
 lazy_static = "1.5"
-regex = "1.11"
+regex = { version = "1.11", optional = true }
 rand = { version = "0.8", optional = true }
 
 [features]
-default = ["random"]
-random = ["dep:rand"]
+default = ["rand", "regex"]
+rand = ["dep:rand"]
+regex = ["dep:regex"]
diff --git a/talc-std/src/collection.rs b/talc-std/src/collection.rs
index db02366..985cdbc 100644
--- a/talc-std/src/collection.rs
+++ b/talc-std/src/collection.rs
@@ -5,7 +5,8 @@ use talc_lang::{
 	symbol::{symbol, SYM_TYPE_ERROR, SYM_VALUE_ERROR},
 	throw,
 	value::{function::NativeFunc, Value},
-	vmcall, Vm,
+	vm::Vm,
+	vmcall,
 };
 use talc_macros::native_func;
 
diff --git a/talc-std/src/exception.rs b/talc-std/src/exception.rs
index 98ea0f7..a6e9bfd 100644
--- a/talc-std/src/exception.rs
+++ b/talc-std/src/exception.rs
@@ -2,7 +2,7 @@ use talc_lang::{
 	exception::{throw, Exception, Result},
 	symbol::{SYM_TYPE_ERROR, SYM_VALUE_ERROR},
 	value::Value,
-	Vm,
+	vm::Vm,
 };
 use talc_macros::native_func;
 
diff --git a/talc-std/src/file.rs b/talc-std/src/file.rs
index ee3ba62..6d89ce2 100644
--- a/talc-std/src/file.rs
+++ b/talc-std/src/file.rs
@@ -16,7 +16,7 @@ use talc_lang::{
 	symbol::{symbol, Symbol, SYM_TYPE_ERROR, SYM_VALUE_ERROR},
 	throw,
 	value::{function::NativeFunc, HashValue, NativeValue, Value},
-	Vm,
+	vm::Vm,
 };
 use talc_macros::native_func;
 
diff --git a/talc-std/src/format.rs b/talc-std/src/format.rs
index afc9829..3f6f9ab 100644
--- a/talc-std/src/format.rs
+++ b/talc-std/src/format.rs
@@ -7,7 +7,7 @@ use talc_lang::{
 	symbol::SYM_TYPE_ERROR,
 	throw,
 	value::{Complex64, Rational64, Value},
-	Vm,
+	vm::Vm,
 };
 use talc_macros::native_func;
 
diff --git a/talc-std/src/io.rs b/talc-std/src/io.rs
index 8a047ae..f63e559 100644
--- a/talc-std/src/io.rs
+++ b/talc-std/src/io.rs
@@ -10,7 +10,8 @@ use talc_lang::{
 	lstring::LString,
 	symbol::{SYM_TYPE_ERROR, SYM_VALUE_ERROR},
 	value::Value,
-	vmcall, Vm,
+	vm::Vm,
+	vmcall,
 };
 use talc_macros::native_func;
 
diff --git a/talc-std/src/iter.rs b/talc-std/src/iter.rs
index 081a50d..26e3adc 100644
--- a/talc-std/src/iter.rs
+++ b/talc-std/src/iter.rs
@@ -5,7 +5,8 @@ use talc_lang::{
 	symbol::{symbol, SYM_TYPE_ERROR, SYM_VALUE_ERROR},
 	throw,
 	value::{function::NativeFunc, ops::RatioExt, range::RangeType, HashValue, Value},
-	vmcall, vmcalliter, Vm,
+	vm::Vm,
+	vmcall, vmcalliter,
 };
 use talc_macros::native_func;
 
diff --git a/talc-std/src/lib.rs b/talc-std/src/lib.rs
index 1d3a8bb..7195381 100644
--- a/talc-std/src/lib.rs
+++ b/talc-std/src/lib.rs
@@ -2,7 +2,7 @@
 
 use talc_lang::{
 	symbol::{symbol, Symbol},
-	Vm,
+	vm::Vm,
 };
 
 pub mod collection;
@@ -12,25 +12,29 @@ pub mod format;
 pub mod io;
 pub mod iter;
 pub mod num;
-#[cfg(feature = "random")]
-pub mod random;
-pub mod regex;
 pub mod string;
 pub mod value;
 
+#[cfg(feature = "rand")]
+pub mod random;
+#[cfg(feature = "regex")]
+pub mod regex;
+
 pub fn load_all(vm: &mut Vm) {
-	value::load(vm);
-	exception::load(vm);
-	iter::load(vm);
 	collection::load(vm);
-	num::load(vm);
-	io::load(vm);
-	string::load(vm);
-	format::load(vm);
-	regex::load(vm);
+	exception::load(vm);
 	file::load(vm);
-	#[cfg(feature = "random")]
+	format::load(vm);
+	io::load(vm);
+	iter::load(vm);
+	num::load(vm);
+	string::load(vm);
+	value::load(vm);
+
+	#[cfg(feature = "rand")]
 	random::load(vm);
+	#[cfg(feature = "regex")]
+	regex::load(vm);
 }
 
 lazy_static::lazy_static! {
diff --git a/talc-std/src/num.rs b/talc-std/src/num.rs
index 4109826..f33155e 100644
--- a/talc-std/src/num.rs
+++ b/talc-std/src/num.rs
@@ -7,7 +7,8 @@ use talc_lang::{
 	symbol::{Symbol, SYM_TYPE_ERROR, SYM_VALUE_ERROR},
 	throw,
 	value::{ops::RatioExt, Complex64, Value},
-	vmcalliter, Vm,
+	vm::Vm,
+	vmcalliter,
 };
 use talc_macros::native_func;
 
diff --git a/talc-std/src/random.rs b/talc-std/src/random.rs
index 72f1826..6ead898 100644
--- a/talc-std/src/random.rs
+++ b/talc-std/src/random.rs
@@ -4,7 +4,8 @@ use talc_lang::{
 	symbol::{SYM_TYPE_ERROR, SYM_VALUE_ERROR},
 	throw,
 	value::{range::RangeType, Value},
-	vmcalliter, Vm,
+	vm::Vm,
+	vmcalliter,
 };
 use talc_macros::native_func;
 
diff --git a/talc-std/src/regex.rs b/talc-std/src/regex.rs
index 2c74310..48ddead 100644
--- a/talc-std/src/regex.rs
+++ b/talc-std/src/regex.rs
@@ -8,7 +8,7 @@ use talc_lang::{
 	symbol::{Symbol, SYM_TYPE_ERROR, SYM_VALUE_ERROR},
 	throw,
 	value::{NativeValue, Value},
-	Vm,
+	vm::Vm,
 };
 use talc_macros::native_func;
 
diff --git a/talc-std/src/string.rs b/talc-std/src/string.rs
index 4304d11..6efa92c 100644
--- a/talc-std/src/string.rs
+++ b/talc-std/src/string.rs
@@ -4,7 +4,7 @@ use talc_lang::{
 	symbol::{SYM_TYPE_ERROR, SYM_VALUE_ERROR},
 	throw,
 	value::Value,
-	Vm,
+	vm::Vm,
 };
 use talc_macros::native_func;
 
diff --git a/talc-std/src/value.rs b/talc-std/src/value.rs
index e509b78..a6c7f32 100644
--- a/talc-std/src/value.rs
+++ b/talc-std/src/value.rs
@@ -7,7 +7,7 @@ use talc_lang::{
 	symbol::{symbol, Symbol, SYM_TYPE_ERROR, SYM_VALUE_ERROR},
 	throw,
 	value::{ops::RatioExt, HashValue, Rational64, Value},
-	Vm,
+	vm::Vm,
 };
 use talc_macros::native_func;