Remove Quote from parser

Dropped to make the language simpler.

5 files changed, 2 insertions, 213 deletions

diff --git a/compiler/src/ast/parser.rs b/compiler/src/ast/parser.rs
index 33b36be..bb4e0ce 100644
--- a/compiler/src/ast/parser.rs
+++ b/compiler/src/ast/parser.rs
@@ -119,15 +119,6 @@ where
                 self.consume();
                 return Err(Spanned::new(Error::UnexpectedRightPar, span));
             }
-            Token::Quote => {
-                self.consume();
-                let quote = Spanned::new(Expr::Atom(Atom::Symbol("quote".into())), span);
-                let expr = self.parse_expr()?;
-                Spanned::new(
-                    Expr::List(vec![quote, expr]),
-                    Span::new(span.start, self.last_token_span.end),
-                )
-            }
             Token::Number(number) => {
                 self.consume();
                 let atom = parse_number(number).map_err(|e| Spanned::new(e, span))?;
diff --git a/compiler/src/ast/tests.rs b/compiler/src/ast/tests.rs
index 8905427..505b075 100644
--- a/compiler/src/ast/tests.rs
+++ b/compiler/src/ast/tests.rs
@@ -1,4 +1,4 @@
-use std::{fmt::Debug, iter::repeat_n, rc::Rc};
+use std::{fmt::Debug, iter::repeat_n};
 
 use crate::{
     ast::{Atom, Error, Expr, Parser, parser::MAX_DEPTH, tests::E::*},
@@ -263,53 +263,6 @@ fn test_lists() {
     }
 }
 
-fn quote(expr: E) -> E {
-    List(vec![Sym("quote"), expr])
-}
-
-#[test]
-fn test_quote() {
-    let cases = vec![
-        // 'x -> (quote x)
-        (vec![Quote, Symbol("x")], vec![quote(Sym("x"))]),
-        // '42 -> (quote 42)
-        (vec![Quote, Number("42")], vec![quote(Int(42))]),
-        // '() -> (quote nil)
-        (vec![Quote, LeftPar, RightPar], vec![quote(Nil)]),
-        // ''x -> (quote (quote x))
-        (
-            vec![Quote, Quote, Symbol("x")],
-            vec![quote(quote(Sym("x")))],
-        ),
-        // '''x -> (quote (quote (quote x)))
-        (
-            vec![Quote, Quote, Quote, Symbol("x")],
-            vec![quote(quote(quote(Sym("x"))))],
-        ),
-        // '(1 2) -> (quote (1 2))
-        (
-            vec![Quote, LeftPar, Number("1"), Number("2"), RightPar],
-            vec![quote(List(vec![Int(1), Int(2)]))],
-        ),
-        // (list 'a 'b) -> (list (quote a) (quote b))
-        (
-            vec![
-                LeftPar,
-                Symbol("list"),
-                Quote,
-                Symbol("a"),
-                Quote,
-                Symbol("b"),
-                RightPar,
-            ],
-            vec![List(vec![Sym("list"), quote(Sym("a")), quote(Sym("b"))])],
-        ),
-    ];
-    for (tokens, expected) in cases {
-        assert_eq!(parse(tokens.clone()), expected, "input: {tokens:?}");
-    }
-}
-
 #[test]
 fn test_top_level() {
     let cases = vec![
@@ -344,8 +297,6 @@ fn test_unexpected_right_par() {
         vec![RightPar],
         vec![Number("1"), RightPar],
         vec![LeftPar, Symbol("a"), RightPar, RightPar],
-        vec![Quote, RightPar],
-        vec![LeftPar, Quote, Quote, RightPar],
     ];
     for tokens in cases {
         assert_eq!(
@@ -373,24 +324,6 @@ fn test_unclosed_left_par() {
 }
 
 #[test]
-fn test_unexpected_eof_after_quote() {
-    let cases = vec![
-        vec![Quote],
-        vec![Quote, Quote],
-        vec![Symbol("a"), Quote],
-        vec![LeftPar, Quote],
-        vec![Quote, LeftPar, Quote],
-    ];
-    for tokens in cases {
-        assert_eq!(
-            parse_err(tokens.clone()),
-            Error::UnexpectedEof,
-            "input: {tokens:?}"
-        );
-    }
-}
-
-#[test]
 fn test_invalid_integer() {
     let cases = vec![
         "99999999999999999999",
@@ -553,63 +486,6 @@ fn test_span_empty_list_covers_parens() {
 }
 
 #[test]
-fn test_span_quote_atom() {
-    // 'x -> outer = [0..2]; Sym(quote) = [0..1]; x = [1..2]
-    let q = sp((1, 0, 0), (1, 1, 1));
-    let x = sp((1, 1, 1), (1, 2, 2));
-    let tokens = vec![tsp(Quote, q), tsp(Symbol("x"), x)];
-    let prog = parse_sp(tokens.clone());
-
-    assert_eq!(prog[0].span, sp((1, 0, 0), (1, 2, 2)), "input: {tokens:?}");
-
-    if let Expr::List(items) = &prog[0].inner {
-        assert_eq!(
-            items[0].inner,
-            Expr::Atom(Atom::Symbol(Rc::from("quote"))),
-            "input: {tokens:?}",
-        );
-        assert_eq!(items[0].span, q, "input: {tokens:?}");
-        assert_eq!(items[1].span, x, "input: {tokens:?}");
-    } else {
-        panic!("expected list, input: {tokens:?}");
-    }
-}
-
-#[test]
-fn test_span_quote_of_list() {
-    // '(quote x)
-    //  0 1 2..7 8 9 10
-    let q = sp((1, 0, 0), (1, 1, 1));
-    let lp = sp((1, 1, 1), (1, 2, 2));
-    let q_sym = sp((1, 2, 2), (1, 7, 7));
-    let x_sym = sp((1, 8, 8), (1, 9, 9));
-    let rp = sp((1, 9, 9), (1, 10, 10));
-
-    let tokens = vec![
-        tsp(Quote, q),
-        tsp(LeftPar, lp),
-        tsp(Symbol("quote"), q_sym),
-        tsp(Symbol("x"), x_sym),
-        tsp(RightPar, rp),
-    ];
-    let prog = parse_sp(tokens.clone());
-
-    let outer = &prog[0]; // (quote (quote x))
-    assert_eq!(outer.span, sp((1, 0, 0), (1, 10, 10)), "input: {tokens:?}");
-
-    if let Expr::List(items) = &outer.inner {
-        assert_eq!(items[0].span, q, "input: {tokens:?}");
-        assert_eq!(
-            items[1].span,
-            sp((1, 1, 1), (1, 10, 10)),
-            "input: {tokens:?}"
-        );
-    } else {
-        panic!("expected list, input: {tokens:?}");
-    }
-}
-
-#[test]
 fn test_error_span_unexpected_right_par() {
     let s = sp((1, 5, 5), (1, 6, 6));
     let tokens = vec![tsp(RightPar, s)];
@@ -664,16 +540,6 @@ fn test_error_span_unclosed_left_par_nested() {
 }
 
 #[test]
-fn test_error_span_unexpected_eof_after_quote() {
-    let q = sp((1, 0, 0), (1, 1, 1));
-    let tokens = vec![tsp(Quote, q)];
-    let err = parse_sp_err(tokens.clone());
-
-    assert_eq!(err.inner, Error::UnexpectedEof, "input: {tokens:?}");
-    assert_eq!(err.span, q, "input: {tokens:?}");
-}
-
-#[test]
 fn test_error_span_unclosed_string() {
     let s = sp((1, 0, 0), (1, 7, 7));
     let tokens = vec![tsp(UnclosedString("oops"), s)];
diff --git a/compiler/src/lex/lexer.rs b/compiler/src/lex/lexer.rs
index 801d382..6efbca0 100644
--- a/compiler/src/lex/lexer.rs
+++ b/compiler/src/lex/lexer.rs
@@ -4,7 +4,7 @@ use crate::{
 };
 
 fn is_terminator(ch: char) -> bool {
-    ch.is_whitespace() || matches!(ch, '(' | ')' | '\'' | '"' | ';')
+    ch.is_whitespace() || matches!(ch, '(' | ')' | '"' | ';')
 }
 
 pub struct Lexer<'a> {
@@ -128,10 +128,6 @@ impl<'a> Iterator for Lexer<'a> {
                 self.consume();
                 Token::RightPar
             }
-            '\'' => {
-                self.consume();
-                Token::Quote
-            }
 
             // Number
             ch if ch.is_ascii_digit()
diff --git a/compiler/src/lex/tests.rs b/compiler/src/lex/tests.rs
index 2d872a2..d0ed658 100644
--- a/compiler/src/lex/tests.rs
+++ b/compiler/src/lex/tests.rs
@@ -38,24 +38,6 @@ fn test_parens() {
 }
 
 #[test]
-fn test_quote() {
-    let cases = vec![
-        ("'", vec![Quote]),
-        ("'a", vec![Quote, Symbol("a")]),
-        ("''a", vec![Quote, Quote, Symbol("a")]),
-        ("'()", vec![Quote, LeftPar, RightPar]),
-        (
-            "'(1 2)",
-            vec![Quote, LeftPar, Number("1"), Number("2"), RightPar],
-        ),
-        ("(' )", vec![LeftPar, Quote, RightPar]),
-    ];
-    for (code, tokens) in cases {
-        assert_eq!(tokenize(code), tokens);
-    }
-}
-
-#[test]
 fn test_numbers() {
     let cases = vec![
         ("0", vec![Number("0")]),
@@ -83,7 +65,6 @@ fn test_strings() {
         (r#""hello""#, vec![String("hello")]),
         (r#""hello world""#, vec![String("hello world")]),
         (r#""(not a list)""#, vec![String("(not a list)")]),
-        (r#""'not a quote""#, vec![String("'not a quote")]),
         (r#""; not a comment""#, vec![String("; not a comment")]),
         (r#""  spaces  ""#, vec![String("  spaces  ")]),
     ];
@@ -96,7 +77,6 @@ fn test_strings() {
 fn test_string_escapes() {
     let cases = vec![
         (r#""line\nbreak""#, vec![String(r"line\nbreak")]),
-        (r#""with \"quotes\"""#, vec![String(r#"with \"quotes\""#)]),
         (r#""\\""#, vec![String(r"\\")]),
         ("\"single\\\nline\"", vec![String("single\\\nline")]),
     ];
@@ -169,7 +149,6 @@ fn test_no_separators() {
         ("(foo)", vec![LeftPar, Symbol("foo"), RightPar]),
         ("(1)", vec![LeftPar, Number("1"), RightPar]),
         ("(a)b", vec![LeftPar, Symbol("a"), RightPar, Symbol("b")]),
-        ("'(a)", vec![Quote, LeftPar, Symbol("a"), RightPar]),
         (r#"("s")"#, vec![LeftPar, String("s"), RightPar]),
     ];
     for (code, tokens) in cases {
@@ -212,23 +191,6 @@ fn test_expressions() {
             vec![LeftPar, Symbol("+"), Number("1"), Number("2"), RightPar],
         ),
         (
-            "(if (= x 0) 'zero 'nonzero)",
-            vec![
-                LeftPar,
-                Symbol("if"),
-                LeftPar,
-                Symbol("="),
-                Symbol("x"),
-                Number("0"),
-                RightPar,
-                Quote,
-                Symbol("zero"),
-                Quote,
-                Symbol("nonzero"),
-                RightPar,
-            ],
-        ),
-        (
             r#"(print "hello, world")"#,
             vec![LeftPar, Symbol("print"), String("hello, world"), RightPar],
         ),
@@ -248,17 +210,6 @@ fn test_expressions() {
                 RightPar,
             ],
         ),
-        (
-            "'(1 2 3)",
-            vec![
-                Quote,
-                LeftPar,
-                Number("1"),
-                Number("2"),
-                Number("3"),
-                RightPar,
-            ],
-        ),
     ];
     for (code, tokens) in cases {
         assert_eq!(tokenize(code), tokens);
@@ -367,17 +318,3 @@ fn test_span_after_comment() {
     let s = spans("; cm\nfoo");
     assert_eq!(s, vec![(Pos::new(2, 0, 5), Pos::new(2, 3, 8))]);
 }
-
-#[test]
-fn test_span_after_quote() {
-    // 'hello
-    // 0123456
-    let s = spans("'hello");
-    assert_eq!(
-        s,
-        vec![
-            (Pos::new(1, 0, 0), Pos::new(1, 1, 1)),
-            (Pos::new(1, 1, 1), Pos::new(1, 6, 6))
-        ]
-    );
-}
diff --git a/compiler/src/lex/token.rs b/compiler/src/lex/token.rs
index 2d07885..910c8ff 100644
--- a/compiler/src/lex/token.rs
+++ b/compiler/src/lex/token.rs
@@ -2,7 +2,6 @@
 pub enum Token<'a> {
     LeftPar,
     RightPar,
-    Quote,
     Number(&'a str),
     String(&'a str),
     UnclosedString(&'a str),