Macro

Cargo.lock

@@ -55,6 +55,26 @@ dependencies = [
  "hashbrown",
 ]
 
+[[package]]
+name = "literify"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fd552332051e9b3db140d34a371dcc0ed378b72a9227b5273070af58ea34abf4"
+dependencies = [
+ "litrs",
+ "proc-macro2",
+ "quote",
+]
+
+[[package]]
+name = "litrs"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4f17c3668f3cc1132437cdadc93dab05e52d592f06948d3f64828430c36e4a70"
+dependencies = [
+ "proc-macro2",
+]
+
 [[package]]
 name = "logos"
 version = "0.13.0"
@@ -93,6 +113,12 @@ version = "1.18.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "dd8b5dd2ae5ed71462c540258bedcb51965123ad7e7ccf4b9a8cafaa4a63576d"
 
+[[package]]
+name = "paste"
+version = "1.0.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "de3145af08024dea9fa9914f381a17b8fc6034dfb00f3a84013f7ff43f29ed4c"
+
 [[package]]
 name = "proc-macro2"
 version = "1.0.67"
@@ -123,7 +149,9 @@ version = "0.1.0"
 dependencies = [
  "bumpalo",
  "lasso",
+ "literify",
  "logos",
+ "paste",
 ]
 
 [[package]]

Cargo.toml

@@ -4,6 +4,8 @@ version = "0.1.0"
 edition = "2021"
 
 [dependencies]
-bumpalo = { version = "3", features = ["collections"] }
+bumpalo  = { version = "3", features = ["collections"] }
-lasso   = "0.7"
+lasso    = "0.7"
-logos   = "0.13"
+literify = "0.2"
+logos    = "0.13"
+paste    = "1.0"

src/main.rs

@@ -3,6 +3,7 @@
 mod syntax;
 mod utils;
 
+use bumpalo::Bump;
 use std::io::{stdin, Read};
 use utils::default;
 
@@ -10,5 +11,7 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
     let mut buf = default();
     stdin().read_to_string(&mut buf)?;
 
+    let arena = Bump::new();
+    println!("{:?}", syntax::parser::parse(&buf, &arena));
     Ok(())
 }

src/syntax/ast.rs

@@ -44,15 +44,10 @@ pub enum Expr<'a> {
     Call(ExprRef<'a>, ExprList<'a>),
     Binary(Spanned<BinaryOp>, ExprRef<'a>, ExprRef<'a>),
     Unary(Spanned<UnaryOp>, ExprRef<'a>),
-    Def {
-        kind:  DefKind,
-        ident: Spanned<Ident>,
-        ty:    Option<Spanned<Type>>,
-        init:  Option<ExprRef<'a>>,
-    },
     Set(ExprRef<'a>, ExprRef<'a>),
     Loop(ExprList<'a>),
     Block(ExprList<'a>),
+    Definition(Definition<'a>),
     Switch {
         on:       ExprRef<'a>,
         branches: &'a [(Spanned<Switcher>, ExprRef<'a>)],
@@ -62,15 +57,25 @@ pub enum Expr<'a> {
         branches: &'a [(ExprRef<'a>, ExprRef<'a>)],
         else_:    ExprRef<'a>,
     },
+    Break(Option<ExprRef<'a>>),
+    Return(Option<ExprRef<'a>>),
+    Continue,
+}
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub enum Definition<'a> {
+    Binding {
+        kind:  DefKind,
+        ident: Spanned<Ident>,
+        ty:    Option<Spanned<Type>>,
+        init:  Option<ExprRef<'a>>,
+    },
     Func {
         ident:  Spanned<Ident>,
         params: &'a [(Spanned<Ident>, Spanned<Type>)],
         ret:    Spanned<Type>,
         body:   ExprList<'a>,
     },
-    Break(Option<ExprRef<'a>>),
-    Return(Option<ExprRef<'a>>),
-    Continue,
 }
 
 #[derive(Clone, Copy, Debug, PartialEq, Eq)]

src/syntax/mod.rs

@@ -1,2 +1,3 @@
 pub mod ast;
+pub mod parser;
 pub mod token;

src/syntax/parser.rs

@@ -0,0 +1,63 @@
+use bumpalo::Bump;
+use logos::Logos;
+
+use super::{
+    ast::{Definition, Spanned},
+    token::Token,
+};
+
+type Lexer<'a> = logos::Lexer<'a, Token>;
+
+macro_rules! extract {
+    (
+        $self:expr,
+        $(pat:pat),* $(,)?
+    ) => {
+
+    };
+}
+
+struct Parser<'a, 'l> {
+    arena: &'a Bump,
+    lexer: Lexer<'l>,
+}
+
+impl<'a, 'l> Parser<'a, 'l> {
+    /// Poll next token
+    fn next(&mut self) -> Result<Token> {
+        match self.lexer.next() {
+            Some(Ok(token)) => Ok(token),
+            Some(Err(())) => Err(ErrorKind::InvalidToken),
+            None => Err(ErrorKind::UnexpectedEnd),
+        }
+        .map_err(|k| Spanned::new(k, self.lexer.span()))
+    }
+
+    /// Form an error
+    #[inline]
+    fn error(&self, kind: ErrorKind) -> Error {
+        Spanned::new(kind, self.lexer.span())
+    }
+
+    /// Parse everything or DIE!
+    fn run(self) -> Result<&'a [Definition<'a>]> {
+        Ok(self.arena.alloc_slice_copy(&[]))
+    }
+}
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub enum ErrorKind {
+    InvalidToken,
+    UnexpectedEnd,
+}
+
+pub type Error = Spanned<ErrorKind>;
+type Result<T, E = Error> = std::result::Result<T, E>;
+
+pub fn parse<'a>(code: &str, arena: &'a Bump) -> Result<&'a [Definition<'a>]> {
+    Parser {
+        arena,
+        lexer: Token::lexer(code),
+    }
+    .run()
+}

src/syntax/token.rs

@@ -6,53 +6,72 @@ pub struct Extras {
     pub interner: Rodeo,
 }
 
-#[derive(Clone, Copy, Debug, PartialEq, Eq, Logos)]
+macro_rules! token_def {
-#[logos(extras = Extras)]
+    (
-#[logos(skip r"[ \t\n\f]+")]
+        unit    { $($u_name:ident : $($u_tok:literal),* $(,)?;)* }
-#[logos(skip r"\\.*")]
+        keyword { $($kw:tt),* $(,)* }
-#[rustfmt::skip]
+        else    { $($e_tt:tt)* }
-pub enum Token {
+    ) => {
-    #[token("(")] LeftParen,
+        literify::literify! (paste::paste! {
-    #[token(")")] RightParen,
+            #[derive(Clone, Copy, Debug, PartialEq, Eq, Logos)]
-    #[token("{")] LeftCurly,
+            #[logos(extras = Extras)]
-    #[token("}")] RightCurly,
+            #[logos(skip r"[ \t\n\f]+")]
-    #[token(".")] Dot,
+            #[logos(skip r"\\.*")]
-    #[token(",")] Comma,
+            pub enum Token {
-    #[token(":")] Colon,
+                $(
-    #[token(";")] Semicolon,
+                    $(#[token($u_tok)])*
+                    $u_name,
+                )*
 
-    #[token("←")] //______
+                $(
-    #[token("<-")] LArrow,
+                    #[token(~($kw))]
-    #[token("→")] //______
+                    [<$kw:camel>],
-    #[token("->")] RArrow,
+                )*
 
-    #[token("+")] Plus,
+                $($e_tt)*
-    #[token("-")] Minus,
+            }
-    #[token("*")] Star,
-    #[token("/")] Slash,
 
-    #[token("=")] Equ,
+            macro_rules! T {
-    #[token("≠")] //___
+                $($(
-    #[token("/=")] Neq,
+                    ($u_tok) => { $crate::syntax::token::Token::$u_name };
-    #[token("<")] Lt,
+                )*)*
-    #[token(">")] Gt,
+            }
-    #[token("≤")] //____
+        });
-    #[token("<=")] LtEq,
+    };
-    #[token("≥")] //____
+}
-    #[token(">=")] GtEq,
 
-    #[token("func")] Func,
+token_def!(
-    #[token("var")] Var,
+    unit {
-    #[token("const")] Const,
+        LeftParen : "(";
-    #[token("include")] Include,
+        RightParen: ")";
-    #[token("switch")] Switch,
+        LeftCurly : "{";
-    #[token("loop")] Loop,
+        RightCurly: "}";
-    #[token("return")] Return,
+        Dot       : ".";
-    #[token("break")] Break,
+        Comma     : ",";
-    #[token("continue")] Continue,
+        Colon     : ":";
-    #[token("uninit")] Uninit,
+        Semicolon : ";";
-    #[token("asm")] Asm,
 
+        LArrow: "←", "<-";
+        RArrow: "→", "->";
+
+        Plus   : "+";
+        Minus  : "-";
+        Star   : "*";
+        Slash  : "/";
+        Precent: "%";
+
+        Equ  : "=";
+        Neq  : "≠", "/=";
+        Lt   : "<";
+        Gt   : ">";
+        LtEq : "≤", "<=";
+        GtEq : "≥", ">=";
+    }
+
+    keyword { func, var, const, include, switch, loop,
+              return, break, continue, uninit, asm }
+
+    else {
     #[regex(
         r"\p{XID_Start}\p{XID_Continue}*",
         |l| intern(l, l.slice()),
@@ -70,7 +89,10 @@ pub enum Token {
         "[0-9]+",
         |l| l.slice().parse::<u64>().ok()
     )] Int(u64),
-}
+    }
+);
+
+pub(crate) use T;
 
 fn intern(lexer: &mut Lexer<'_, Token>, s: &str) -> Spur {
     lexer.extras.interner.get_or_intern(s)