a

flake.nix

@@ -9,28 +9,25 @@
       inputs.nixpkgs.follows = "nixpkgs";
     };
 
-    fenix = {
+    rust-overlay = {
-      url = github:nix-community/fenix;
+      url = github:oxalica/rust-overlay;
       inputs.nixpkgs.follows = "nixpkgs";
     };
 
     flake-utils.url = github:numtide/flake-utils;
   };
 
-  outputs = inputs@{ self, nixpkgs, crane, fenix, flake-utils }:
+  outputs = inputs@{ self, nixpkgs, crane, rust-overlay, flake-utils }:
     flake-utils.lib.eachDefaultSystem (system:
       let
         pkgs = import nixpkgs {
           inherit system;
-          overlays = [ fenix.overlays.default ];
+          overlays = [ rust-overlay.overlays.default ];
         };
 
         inherit (pkgs) lib;
 
-        toolchain = pkgs.fenix.fromToolchainFile {
+        toolchain = pkgs.rust-bin.fromRustupToolchainFile ./rust-toolchain.toml;
-          file = ./rust-toolchain.toml;
-          sha256 = "sha256-n8LtGbpj/yCUGo0NFJ7FNv9fSdT9oKEUl+EPLg06JdQ=";
-        };
 
         craneLib = (crane.mkLib pkgs).overrideToolchain toolchain;
         src = craneLib.cleanCargoSource (craneLib.path ./.);

src/args.rs

@@ -1,5 +1,4 @@
 use std::env;
-use std::path::PathBuf;
 use std::process::exit;
 
 const VERSION: &str = env!("CARGO_PKG_VERSION");
@@ -9,7 +8,7 @@ const CRATE: &str = env!("CARGO_CRATE_NAME");
 #[derive(Default)]
 pub struct Args {
     version: bool,
-    file: Option<PathBuf>,
+    file: Option<String>,
 }
 
 impl Args {
@@ -35,7 +34,7 @@ impl Args {
                     if self.file.is_some() {
                         panic!("please specify only a single source file!");
                     }
-                    self.file = Some(PathBuf::from(file));
+                    self.file = Some(file.to_owned());
                 }
             }
         }
@@ -56,7 +55,7 @@ impl Args {
     /// Fetches the file from the arguments.
     /// Panics if there is no file in the arguments
     #[inline]
-    pub fn get_file(self) -> PathBuf {
+    pub fn get_file(self) -> String {
         self.file.expect("no file supplied!")
     }
 }

src/ast.rs

@@ -1,132 +1,89 @@
-//! A very naive AST definition using recursive enums
+/// A very naive AST definition using recursive enums
-//!
+/// See the parser for implementation
-//! See the parser for implementation
 
 use std::rc::Rc;
 
 pub type Parent = Vec<Entity>;
 
 /// Entities are functions, classes, and modules
-#[derive(Debug, PartialEq)]
+#[derive(Debug)]
 pub enum Entity {
     Fn(Fn),
     Class(Class),
     Module(Module),
-    Static(Let),
 }
 
-/// A module just provides an additional scope
+#[derive(Debug)]
-///
-/// TODO: Add exporting and importing modules
-#[derive(Debug, PartialEq)]
 pub struct Module {
-    /// Name of module
     pub name: Rc<str>,
-    /// Everything inside the module
     pub children: Vec<ModuleChildren>,
 }
 
 /// Modules contain functions, classes and statements
-#[derive(Debug, PartialEq)]
+#[derive(Debug)]
 pub enum ModuleChildren {
     Fn(Fn),
     Class(Class),
-    Module(Module),
+    Statement(Statement),
-    Static(Let),
 }
 
-/// Classes encapsulate functions and definitions.
+#[derive(Debug)]
-#[derive(Debug, PartialEq)]
 pub struct Class {
-    /// Name of class
     pub name: Rc<str>,
-    /// Everything inside the class
     pub children: Vec<ClassChildren>,
 }
 
-#[derive(Debug, PartialEq)]
+/// Classes contain functions and statements.
+///
+/// TODO: Maybe change statements to something else
+#[derive(Debug)]
 pub enum ClassChildren {
     Fn(Fn),
-    Let(Let),
+    Statement(Statement),
-    Static(Let),
 }
 
-/// A Function
+#[derive(Debug)]
-#[derive(Debug, PartialEq)]
 pub struct Fn {
-    /// Name of the function
     pub name: Rc<str>,
-    /// Optional return type
+    pub return_typ: Option<Primitive>,
-    pub return_ty: Option<Ty>,
+    pub params: Vec<(Rc<str>, Primitive)>,
-    /// Parameters
-    pub params: Vec<(Rc<str>, Ty)>,
-    /// The function block
     pub children: Vec<Statement>,
 }
 
-/// Statements encapsulate expressions and definitions
+#[derive(Debug)]
-#[derive(Debug, PartialEq)]
 pub enum Statement {
-    Static(Let),
     Let(Let),
     Expr(Expr),
+    Block(Vec<Statement>),
 }
 
-/// A variable definition
+#[derive(Debug)]
-#[derive(Debug, PartialEq)]
 pub struct Let {
-    /// Name of variabe
     pub name: Rc<str>,
-    /// Type of variable
+    pub typ: Primitive,
-    pub ty: Ty,
-    /// Value of variable
     pub expr: Option<Expr>,
 }
 
+type Op = crate::lexer::TokenSymbol;
+
+#[derive(Debug)]
+pub enum Expr {
+    Int(i32),
+    Float(f32),
+    Char(char),
+    Op(Op, Box<Expr>, Option<Box<Expr>>),
+    If(Box<Expr>, Box<Expr>, Option<Box<Expr>>),
+    Loop,
+    Break,
+    Continue,
+}
+
 /// Primitives
 ///
 /// TODO: add arrays and pointers maybe
-#[derive(Debug, PartialEq)]
+#[derive(Debug)]
-pub enum Ty {
+pub enum Primitive {
     Int,
     Float,
     Char,
 }
-
-#[derive(Debug, PartialEq)]
-pub struct If {
-    pub cond: Box<Expr>,
-    pub then: Vec<Statement>,
-    pub or: Option<Box<ElseType>>,
-}
-
-#[derive(Debug, PartialEq)]
-pub enum ElseType {
-    If(If),
-    Else(Vec<Statement>),
-}
-
-pub(crate) type Op = crate::lexer::TokenSymbol;
-
-#[derive(Debug, PartialEq)]
-pub enum Literal {
-    Int(i32),
-    Float(f32),
-    Char(char),
-}
-
-/// Lowest form of expression
-///
-/// TODO: refine
-#[derive(Debug, PartialEq)]
-pub enum Expr {
-    Literal(Literal),
-    Identifier(Rc<str>),
-    Op(Op, Box<Expr>, Option<Box<Expr>>),
-    If(If),
-    Block(Vec<Statement>),
-    Loop(Vec<Statement>),
-    Break,
-    Continue,
-    Return(Option<Box<Expr>>),
-}

src/lexer.rs

@@ -6,7 +6,7 @@ use std::str;
 /// All token literals
 ///
 /// TODO: Add string
-#[derive(Debug, PartialEq, Clone, Copy)]
+#[derive(Debug, PartialEq)]
 pub enum TokenLiteral {
     Int,
     Float,
@@ -14,9 +14,11 @@ pub enum TokenLiteral {
 }
 
 /// All token symbols
-#[derive(Debug, PartialEq, Clone, Copy)]
+///
+/// TODO: Maybe add *
+#[derive(Debug, PartialEq)]
 pub enum TokenSymbol {
-    // arithmetic
+    // operators
     Plus,
     Minus,
     Star,
@@ -38,7 +40,9 @@ pub enum TokenSymbol {
 
     // relational
     Gt,
+    Ge,
     Lt,
+    Le,
     GtEq,
     LtEq,
     EqEq,
@@ -65,7 +69,7 @@ pub enum TokenSymbol {
 }
 
 /// All token keywod
-#[derive(Debug, PartialEq, Clone, Copy)]
+#[derive(Debug, PartialEq)]
 pub enum TokenKeyword {
     // parents
     Fn,
@@ -73,7 +77,6 @@ pub enum TokenKeyword {
     Module,
 
     // statements
-    Static,
     Let,
     Ret,
 
@@ -86,7 +89,6 @@ pub enum TokenKeyword {
     Loop,
     Break,
     Continue,
-    Return,
 
     // primitives
     Int,
@@ -97,7 +99,7 @@ pub enum TokenKeyword {
 /// All token delimiters
 ///
 /// TODO: Maybe add \[ and \]
-#[derive(Debug, PartialEq, Clone, Copy)]
+#[derive(Debug, PartialEq)]
 pub enum TokenDelimiter {
     BraceOpen,
     BraceClose,
@@ -106,7 +108,7 @@ pub enum TokenDelimiter {
 }
 
 /// All tokens
-#[derive(Debug, PartialEq, Clone, Copy)]
+#[derive(Debug, PartialEq)]
 pub enum TokenKind {
     Newline,
     Eof,
@@ -136,10 +138,9 @@ pub struct Lexer<'a> {
     /// A peekable double ended queue for the tokens
     tokens: VecDeque<Token>,
     /// Current line number
-    pub(crate) line: usize,
+    pub line: usize,
-    pub(crate) col: usize,
     /// Start character index for the current token
-    start: usize,
+    pub start: usize,
     /// End character index for the current token
     end: usize,
 }
@@ -171,7 +172,6 @@ impl<'a> Lexer<'a> {
             chars: content.chars().peekable(),
             tokens: VecDeque::new(),
             line: 1,
-            col: 1,
             start: 0,
             end: 0,
         }
@@ -198,7 +198,6 @@ impl<'a> Lexer<'a> {
     #[inline]
     fn next(&mut self) -> Option<char> {
         self.end += 1;
-        self.col += 1;
         self.chars.next()
     }
 
@@ -234,16 +233,11 @@ impl<'a> Lexer<'a> {
                 '0'..='9' => {}
                 '.' => {
                     if is_float {
-                        self.error("multiple decimals encountered");
+                        self.error("Multiple decimals encountered");
                         return self.new_token(TokenKind::Invalid);
                     }
                     is_float = true;
                 }
-                'e' | 'E' => {
-                    self.next();
-                    is_float = true;
-                    break;
-                }
                 _ => break,
             }
             self.next();
@@ -265,11 +259,6 @@ impl<'a> Lexer<'a> {
             return self.new_token(TokenKind::Invalid);
         }
 
-        if self.peek() != Some(&'\'') {
-            self.error("Expected '");
-            return self.new_token(TokenKind::Invalid);
-        }
-
         // skip '
         self.next();
 
@@ -279,7 +268,7 @@ impl<'a> Lexer<'a> {
     fn get_alphanumeric(&mut self) -> Token {
         while let Some(c) = self.peek() {
             match c {
-                'a'..='z' | 'A'..='Z' | '0'..='9' | '_' => {}
+                'a'..='z' | 'A'..='Z' | '0'..='9' => {}
                 _ => break,
             }
             self.next();
@@ -292,7 +281,6 @@ impl<'a> Lexer<'a> {
             "fn" => Keyword(Fn),
             "class" => Keyword(Class),
             "module" => Keyword(Module),
-            "static" => Keyword(Static),
             "let" => Keyword(Let),
             "ret" => Keyword(Ret),
             "if" => Keyword(If),
@@ -301,7 +289,6 @@ impl<'a> Lexer<'a> {
             "loop" => Keyword(Loop),
             "break" => Keyword(Break),
             "continue" => Keyword(Continue),
-            "return" => Keyword(Return),
             "int" => Keyword(Int),
             "float" => Keyword(Float),
             "char" => Keyword(Char),
@@ -405,11 +392,10 @@ impl<'a> Lexer<'a> {
                 '\n' => {
                     self.next();
                     self.line += 1;
-                    self.col = 0;
                     self.new_token(TokenKind::Newline)
                 }
                 '0'..='9' => self.get_numeric(),
-                'a'..='z' | 'A'..='Z' | '_' => self.get_alphanumeric(),
+                'a'..='z' | 'A'..='Z' => self.get_alphanumeric(),
                 '\'' => self.get_char(),
                 _ => self.get_symbol(),
             }
@@ -455,7 +441,7 @@ fn test_peek_next() {
 }
 
 #[test]
-fn test_tokens() {
+fn test_tokens_1() {
     let mut lexer = Lexer::new("let test02 = 4 << 1");
 
     use TokenKind::*;
@@ -515,51 +501,9 @@ fn test_tokens_2() {
 }
 
 #[test]
-fn test_tokens_eof() {
+fn test_tokens_3() {
     let mut lexer = Lexer::new("");
 
     assert_eq!(lexer.peek_token().kind, TokenKind::Eof);
     assert_eq!(lexer.next_token().kind, TokenKind::Eof);
 }
-
-#[test]
-fn test_tokens_numeric() {
-    let mut lexer = Lexer::new("3342");
-
-    let token = lexer.next_token();
-    assert_eq!(token.kind, TokenKind::Literal(TokenLiteral::Int));
-    assert_eq!(*token.val, *"3342");
-
-    assert_eq!(lexer.next_token().kind, TokenKind::Eof);
-}
-
-#[test]
-fn test_tokens_numeric_2() {
-    let mut lexer = Lexer::new("334.2e");
-
-    let token = lexer.next_token();
-    assert_eq!(token.kind, TokenKind::Literal(TokenLiteral::Float));
-    assert_eq!(*token.val, *"334.2e");
-
-    assert_eq!(lexer.next_token().kind, TokenKind::Eof);
-}
-
-#[test]
-fn test_tokens_numeric_3() {
-    let mut lexer = Lexer::new("334.2e-5");
-
-    let mut token = lexer.next_token();
-    assert_eq!(token.kind, TokenKind::Literal(TokenLiteral::Float));
-    assert_eq!(*token.val, *"334.2e");
-
-    assert_eq!(
-        lexer.next_token().kind,
-        TokenKind::Symbol(TokenSymbol::Minus)
-    );
-
-    token = lexer.next_token();
-    assert_eq!(token.kind, TokenKind::Literal(TokenLiteral::Int));
-    assert_eq!(*token.val, *"5");
-
-    assert_eq!(lexer.next_token().kind, TokenKind::Eof);
-}

src/lib.rs

@@ -1,4 +1,3 @@
 pub mod args;
 pub mod ast;
 pub mod lexer;
-pub mod parser;

src/main.rs

@@ -4,7 +4,10 @@ use std::{
 };
 
 use tricc::args::Args;
-use tricc::parser::Parser;
+use tricc::lexer::{
+    Lexer,
+    TokenKind,
+};
 
 fn main() {
     panic::set_hook(Box::new(|panic_info| {
@@ -28,13 +31,10 @@ fn main() {
 
     let file = args.get_file();
     let content = fs::read_to_string(&file).expect("Couldn't read the file");
-    let mut parser = Parser::new(&content);
+
-    let Some(parent) = parser.parse() else {
+    let mut lexer = Lexer::new(content.as_str());
-        eprintln!(
+
-            "Failed to parse {} - See the errors above",
+    while lexer.peek_token().kind != TokenKind::Eof {
-            file.to_string_lossy()
+        println!("{:?}", lexer.next_token());
-        );
+    }
-        std::process::exit(1);
-    };
-    println!("Parsed AST:\n{:#?}", parent);
 }

src/parser/entity.rs

@@ -1,215 +0,0 @@
-use super::Parser;
-use crate::ast::*;
-use crate::lexer::{
-    TokenDelimiter,
-    TokenKeyword,
-    TokenKind,
-    TokenSymbol,
-};
-use std::rc::Rc;
-
-impl<'a> Parser<'a> {
-    /// entity ::= module | class | fn | static
-    pub(super) fn parse_entity(&mut self) -> Option<Entity> {
-        use TokenKeyword::*;
-        let token = self.peek_token();
-
-        if let TokenKind::Keyword(keyword) = &token.kind {
-            Some(match keyword {
-                Module => Entity::Module(self.parse_module()?),
-                Class => Entity::Class(self.parse_class()?),
-                Fn => Entity::Fn(self.parse_fn()?),
-                Static => Entity::Static(self.parse_static()?),
-                _ => {
-                    self.error_expected_peek("entity");
-                    return None;
-                }
-            })
-        } else {
-            self.error_expected_peek("entity");
-            None
-        }
-    }
-
-    /// module ::= "module" ident "{" { module | fn | static | class } "}"
-    fn parse_module(&mut self) -> Option<Module> {
-        self.next_token();
-
-        let name = self.parse_ident()?;
-        let mut children = vec![];
-
-        if !self.skip_token(TokenKind::Delimiter(TokenDelimiter::BraceOpen)) {
-            self.error_expected_peek("{");
-            return None;
-        }
-
-        loop {
-            use TokenKeyword::*;
-            self.trim_newlines();
-            if let TokenKind::Keyword(keyword) = &self.peek_token().kind {
-                children.push(match keyword {
-                    Module => ModuleChildren::Module(self.parse_module()?),
-                    Fn => ModuleChildren::Fn(self.parse_fn()?),
-                    Static => ModuleChildren::Static(self.parse_static()?),
-                    Class => ModuleChildren::Class(self.parse_class()?),
-                    _ => {
-                        self.error_expected_peek("module child");
-                        return None;
-                    }
-                });
-                if !self.check_newline_or_tok(TokenKind::Delimiter(TokenDelimiter::BraceClose)) {
-                    self.error_expected_peek("newline or }");
-                    return None;
-                }
-            } else if !self.skip_token(TokenKind::Delimiter(TokenDelimiter::BraceClose)) {
-                self.error_expected_peek("}");
-                return None;
-            } else {
-                break;
-            }
-        }
-
-        Some(Module { name, children })
-    }
-
-    /// class ::= "class" ident "{" { fn | static | let } "}"
-    fn parse_class(&mut self) -> Option<Class> {
-        self.next_token();
-
-        let name = self.parse_ident()?;
-        let mut children = vec![];
-
-        if !self.skip_token(TokenKind::Delimiter(TokenDelimiter::BraceOpen)) {
-            self.error_expected_peek("{");
-            return None;
-        }
-
-        loop {
-            use TokenKeyword::*;
-            self.trim_newlines();
-            if let TokenKind::Keyword(keyword) = &self.peek_token().kind {
-                children.push(match keyword {
-                    Fn => ClassChildren::Fn(self.parse_fn()?),
-                    Static => ClassChildren::Static(self.parse_static()?),
-                    Let => ClassChildren::Let(self.parse_let()?),
-                    _ => {
-                        self.error_expected_peek("class child");
-                        return None;
-                    }
-                });
-                if !self.check_newline_or_tok(TokenKind::Delimiter(TokenDelimiter::BraceClose)) {
-                    self.error_expected_peek("newline or }");
-                    return None;
-                }
-            } else if !self.skip_token(TokenKind::Delimiter(TokenDelimiter::BraceClose)) {
-                self.error_expected_peek("}");
-                return None;
-            } else {
-                break;
-            }
-        }
-
-        Some(Class { name, children })
-    }
-
-    /// fn ::= "fn" ident "(" [ identWithTy { "," identWithTy } ] ")" [ ":" ty ]
-    ///        "{" { statement } "}"
-    fn parse_fn(&mut self) -> Option<Fn> {
-        self.next_token();
-
-        let name = self.parse_ident()?;
-        let mut params: Vec<(Rc<str>, Ty)> = vec![];
-        let mut return_typ: Option<Ty> = None;
-        let mut children: Vec<Statement> = vec![];
-
-        if !self.skip_token(TokenKind::Delimiter(TokenDelimiter::ParenOpen)) {
-            self.error_expected_peek("(");
-            return None;
-        }
-
-        loop {
-            if self.peek_token().kind == TokenKind::Identifier {
-                params.push(self.parse_ident_with_ty()?);
-            }
-
-            if !self.skip_token(TokenKind::Symbol(TokenSymbol::Comma)) {
-                if !self.skip_token(TokenKind::Delimiter(TokenDelimiter::ParenClose)) {
-                    self.error_expected_peek(", or )");
-                    return None;
-                } else {
-                    break;
-                }
-            }
-        }
-
-        if self.skip_token(TokenKind::Symbol(TokenSymbol::Colon)) {
-            return_typ = Some(self.parse_ty()?);
-        }
-
-        if !self.skip_token(TokenKind::Delimiter(TokenDelimiter::BraceOpen)) {
-            self.error_expected_peek("{");
-            return None;
-        }
-
-        loop {
-            self.trim_newlines();
-            if self.skip_token(TokenKind::Delimiter(TokenDelimiter::BraceClose)) {
-                break;
-            }
-            children.push(self.parse_statement()?);
-            if !self.check_newline_or_tok(TokenKind::Delimiter(TokenDelimiter::BraceClose)) {
-                self.error_expected_peek("newline or }");
-                return None;
-            }
-        }
-
-        Some(Fn {
-            name,
-            return_ty: return_typ,
-            params,
-            children,
-        })
-    }
-}
-
-#[test]
-fn test_parse_entity() {
-    let mut parser = Parser::new(
-        r#"module module01 {
-             class class01 {
-               fn fn01(param01: char, param02: float) {
-                 static let let01: int = 4
-               }
-             }
-
-             fn fn02 (): int { }
-          }"#,
-    );
-    assert_eq!(
-        parser.parse_entity(),
-        Some(Entity::Module(Module {
-            name: "module01".into(),
-            children: vec![
-                ModuleChildren::Class(Class {
-                    name: "class01".into(),
-                    children: vec![ClassChildren::Fn(Fn {
-                        name: "fn01".into(),
-                        return_ty: None,
-                        params: vec![("param01".into(), Ty::Char), ("param02".into(), Ty::Float)],
-                        children: vec![Statement::Static(Let {
-                            name: "let01".into(),
-                            ty: Ty::Int,
-                            expr: Some(Expr::Literal(Literal::Int(4)))
-                        })]
-                    })]
-                }),
-                ModuleChildren::Fn(Fn {
-                    name: "fn02".into(),
-                    return_ty: Some(Ty::Int),
-                    params: vec![],
-                    children: vec![]
-                })
-            ]
-        }))
-    );
-}

src/parser/expr.rs

@@ -1,435 +0,0 @@
-use super::Parser;
-use crate::ast::{
-    self,
-    *,
-};
-use crate::lexer::{
-    TokenDelimiter,
-    TokenKeyword,
-    TokenKind,
-    TokenLiteral,
-    TokenSymbol,
-};
-use std::rc::Rc;
-
-impl<'a> Parser<'a> {
-    /// exprIf ::= "if" expr block [ else (block | exprIf ) ]
-    fn parse_expr_if(&mut self) -> Option<If> {
-        // skip "if"
-        self.next_token();
-
-        let cond = Box::new(self.parse_expr()?);
-        let then = self.parse_expr_block()?;
-
-        if !self.skip_token(TokenKind::Keyword(TokenKeyword::Else)) {
-            return Some(If {
-                cond,
-                then,
-                or: None,
-            });
-        }
-
-        if self.peek_token().kind != TokenKind::Keyword(TokenKeyword::If) {
-            return Some(If {
-                cond,
-                then,
-                or: Some(Box::new(ElseType::Else(self.parse_expr_block()?))),
-            });
-        }
-
-        Some(If {
-            cond,
-            then,
-            or: Some(Box::new(ElseType::If(self.parse_expr_if()?))),
-        })
-    }
-
-    /// exprBlock ::= "{" { statement } "}"
-    fn parse_expr_block(&mut self) -> Option<Vec<Statement>> {
-        let mut statements = vec![];
-
-        // skip {
-        self.next_token();
-
-        loop {
-            self.trim_newlines();
-            if self.skip_token(TokenKind::Delimiter(TokenDelimiter::BraceClose)) {
-                break;
-            }
-            statements.push(self.parse_statement()?);
-            if !self.check_newline_or_tok(TokenKind::Delimiter(TokenDelimiter::BraceClose)) {
-                self.error_expected_peek("newline or }");
-                return None;
-            }
-        }
-
-        Some(statements)
-    }
-
-    /// exprLoop ::= "loop" exprBlock
-    fn parse_expr_loop(&mut self) -> Option<Vec<Statement>> {
-        self.next_token();
-        if self.peek_token().kind != TokenKind::Delimiter(TokenDelimiter::BraceOpen) {
-            self.error_expected_peek("{");
-            return None;
-        }
-
-        self.parse_expr_block()
-    }
-
-    /// exprAtom ::= ( "(" expr ")" ) | ident | int | float | char | exprBlock | exprLoop | exprIf
-    fn parse_expr_atom(&mut self) -> Option<Expr> {
-        use ast::Literal::*;
-        use TokenKind::*;
-
-        // TODO: check lvalue validity in the analysis phase
-        Some(match self.peek_token().kind {
-            Delimiter(TokenDelimiter::ParenOpen) => {
-                self.next_token(); // skip (
-
-                let expr = self.parse_expr()?;
-
-                if !self.skip_token(TokenKind::Delimiter(TokenDelimiter::ParenClose)) {
-                    self.error_expected_peek(")");
-                    return None;
-                }
-
-                expr
-            }
-            Identifier => {
-                let token = self.next_token();
-                Expr::Identifier(Rc::clone(&token.val))
-            }
-            Literal(TokenLiteral::Int) => Expr::Literal(Int(self.parse_int()?)),
-            Literal(TokenLiteral::Float) => Expr::Literal(Float(self.parse_float()?)),
-            Literal(TokenLiteral::Char) => Expr::Literal(Char(self.parse_char()?)),
-            Delimiter(TokenDelimiter::BraceOpen) => Expr::Block(self.parse_expr_block()?),
-            Keyword(TokenKeyword::Loop) => Expr::Loop(self.parse_expr_loop()?),
-            Keyword(TokenKeyword::If) => Expr::If(self.parse_expr_if()?),
-            _ => {
-                self.error_expected_peek("expression");
-                return None;
-            }
-        })
-    }
-
-    /// exprUnary ::= [ unaryOp ] exprAtom
-    /// unaryOp   ::= "+" | "-" | "~"
-    fn parse_expr_unary(&mut self) -> Option<Expr> {
-        use TokenSymbol::*;
-        Some(match self.peek_token().kind {
-            TokenKind::Symbol(symbol @ (Minus | Plus | Tilde)) => {
-                self.next_token();
-                Expr::Op(symbol, Box::new(self.parse_expr_atom()?), None)
-            }
-            _ => self.parse_expr_atom()?,
-        })
-    }
-
-    /// exprArithmeticMul ::= exprUnary [ arithmeticMulOp exprArithmeticMul ]
-    /// arithmeticMulOp   ::= "*" | "/" | "%"
-    fn parse_expr_arithmetic_mul(&mut self) -> Option<Expr> {
-        use TokenSymbol::*;
-        let lhs = self.parse_expr_unary()?;
-
-        Some(match self.peek_token().kind {
-            TokenKind::Symbol(symbol @ (Star | Slash | Percent)) => {
-                self.next_token();
-                Expr::Op(
-                    symbol,
-                    Box::new(lhs),
-                    Some(Box::new(self.parse_expr_arithmetic_mul()?)),
-                )
-            }
-            _ => lhs,
-        })
-    }
-
-    /// exprArithmeticAdd ::= exprArithmeticMul [ arithmeticAddOp exprArithmeticAdd ]
-    /// arithmeticAddOp   ::= "+" | "-"
-    fn parse_expr_arithmetic_add(&mut self) -> Option<Expr> {
-        use TokenSymbol::*;
-        let lhs = self.parse_expr_arithmetic_mul()?;
-
-        Some(match self.peek_token().kind {
-            TokenKind::Symbol(symbol @ (Plus | Minus)) => {
-                self.next_token();
-                Expr::Op(
-                    symbol,
-                    Box::new(lhs),
-                    Some(Box::new(self.parse_expr_arithmetic_add()?)),
-                )
-            }
-            _ => lhs,
-        })
-    }
-
-    /// exprBitwiseShift ::= exprArithmeticAdd [ bitwiseShiftOp exprBitwiseShift ]
-    /// bitwiseShiftOp   ::= "<<" | ">>"
-    fn parse_expr_bitwise_shift(&mut self) -> Option<Expr> {
-        use TokenSymbol::*;
-        let lhs = self.parse_expr_arithmetic_add()?;
-
-        Some(match self.peek_token().kind {
-            TokenKind::Symbol(symbol @ (Shl | Shr)) => {
-                self.next_token();
-                Expr::Op(
-                    symbol,
-                    Box::new(lhs),
-                    Some(Box::new(self.parse_expr_bitwise_shift()?)),
-                )
-            }
-            _ => lhs,
-        })
-    }
-
-    /// exprBitwiseAnd ::= exprBitwiseShift [ "&" exprBitwiseAnd ]
-    fn parse_expr_bitwise_and(&mut self) -> Option<Expr> {
-        let lhs = self.parse_expr_bitwise_shift()?;
-        let symbol = TokenSymbol::And;
-
-        if !self.skip_token(TokenKind::Symbol(symbol)) {
-            return Some(lhs);
-        }
-
-        Some(Expr::Op(
-            symbol,
-            Box::new(lhs),
-            Some(Box::new(self.parse_expr_bitwise_and()?)),
-        ))
-    }
-
-    /// exprBitwiseXor ::= exprBitwiseAnd [ "^" exprBitwiseXor ]
-    fn parse_expr_bitwise_xor(&mut self) -> Option<Expr> {
-        let lhs = self.parse_expr_bitwise_and()?;
-        let symbol = TokenSymbol::Caret;
-
-        if !self.skip_token(TokenKind::Symbol(symbol)) {
-            return Some(lhs);
-        }
-
-        Some(Expr::Op(
-            symbol,
-            Box::new(lhs),
-            Some(Box::new(self.parse_expr_bitwise_xor()?)),
-        ))
-    }
-
-    /// exprBiwiseOr ::= exprBitwiseXor [ "|" exprBitwiseOr ]
-    fn parse_expr_bitwise_or(&mut self) -> Option<Expr> {
-        let lhs = self.parse_expr_bitwise_xor()?;
-        let symbol = TokenSymbol::Or;
-
-        if !self.skip_token(TokenKind::Symbol(symbol)) {
-            return Some(lhs);
-        }
-
-        Some(Expr::Op(
-            symbol,
-            Box::new(lhs),
-            Some(Box::new(self.parse_expr_bitwise_or()?)),
-        ))
-    }
-
-    /// exprAssign   ::= exprBitwiseOr [ relationalOp exprRelational ]
-    /// relationalOp ::= ">" | "<" | ">=" | "<=" | "==" | "!="
-    fn parse_expr_relational(&mut self) -> Option<Expr> {
-        use TokenSymbol::*;
-        let lhs = self.parse_expr_bitwise_or()?;
-
-        Some(match self.peek_token().kind {
-            TokenKind::Symbol(symbol @ (Gt | Lt | GtEq | LtEq | EqEq | Ne)) => {
-                self.next_token();
-                Expr::Op(
-                    symbol,
-                    Box::new(lhs),
-                    Some(Box::new(self.parse_expr_relational()?)),
-                )
-            }
-            _ => lhs,
-        })
-    }
-
-    /// exprLogicalAnd ::= exprLogicalRelational [ "&&" exprLogicalAnd ]
-    fn parse_expr_logical_and(&mut self) -> Option<Expr> {
-        let lhs = self.parse_expr_relational()?;
-        let symbol = TokenSymbol::AndAnd;
-
-        if !self.skip_token(TokenKind::Symbol(symbol)) {
-            return Some(lhs);
-        }
-
-        Some(Expr::Op(
-            symbol,
-            Box::new(lhs),
-            Some(Box::new(self.parse_expr_logical_and()?)),
-        ))
-    }
-
-    /// exprLogicalOr ::= exprLogicalAnd [ "||" exprLogicalOr ]
-    fn parse_expr_logical_or(&mut self) -> Option<Expr> {
-        let lhs = self.parse_expr_logical_and()?;
-        let symbol = TokenSymbol::OrOr;
-
-        if !self.skip_token(TokenKind::Symbol(symbol)) {
-            return Some(lhs);
-        }
-
-        Some(Expr::Op(
-            symbol,
-            Box::new(lhs),
-            Some(Box::new(self.parse_expr_logical_or()?)),
-        ))
-    }
-
-    /// exprAssign ::= exprLogicalOr [ assignOp exprAssign ]
-    /// assignOp   ::= "=" | "+=" | "-=" | "*=" | "/=" | "%=" | "^=" | "<<=" | ">>=" | "&=" | "|="
-    fn parse_expr_assign(&mut self) -> Option<Expr> {
-        use TokenSymbol::*;
-        let lhs = self.parse_expr_logical_or()?;
-
-        Some(match self.peek_token().kind {
-            TokenKind::Symbol(
-                symbol @ (Eq | PlusEq | MinusEq | StarEq | SlashEq | PercentEq | CaretEq | ShlEq
-                | ShrEq | AndEq | OrEq),
-            ) => {
-                self.next_token();
-                Expr::Op(
-                    symbol,
-                    Box::new(lhs),
-                    Some(Box::new(self.parse_expr_assign()?)),
-                )
-            }
-            _ => lhs,
-        })
-    }
-
-    /// exprControl ::= "continue" | "break" | "return" [ exprControl ] | exprAssign
-    fn parse_expr_control(&mut self) -> Option<Expr> {
-        use TokenKeyword::*;
-
-        Some(match self.peek_token().kind {
-            TokenKind::Keyword(Continue) => {
-                self.next_token();
-                Expr::Continue
-            }
-            TokenKind::Keyword(Break) => {
-                self.next_token();
-                Expr::Break
-            }
-            TokenKind::Keyword(Return) => {
-                self.next_token();
-                Expr::Return(self.parse_expr_control().map(Box::new))
-            }
-            _ => self.parse_expr_assign()?,
-        })
-    }
-
-    /// entrypoint for expression parsing using recursive descent parsing
-    ///
-    /// <https://en.wikipedia.org/wiki/Recursive_descent_parser>
-    /// expr ::= exprControl
-    pub(super) fn parse_expr(&mut self) -> Option<Expr> {
-        self.parse_expr_control()
-    }
-}
-
-#[test]
-fn test_parse_expr() {
-    use Literal::*;
-    use TokenSymbol::*;
-
-    macro_rules! b {
-        ($expr:expr) => {
-            Box::new($expr)
-        };
-    }
-
-    let mut parser = Parser::new(
-        r#"if if 1 { 1 } else { 0 } + 9 {
-             a = 4
-           } else if 1 {
-             a = 5
-           } else {
-           }
-          amul ^= (4 + 93 * (1 << 3) / 1.44) ^ bhatura
-          stove = { 44 } + amul"#,
-    );
-
-    assert_eq!(
-        parser.parse_expr(),
-        Some(Expr::If(If {
-            cond: b!(Expr::Op(
-                Plus,
-                b!(Expr::If(If {
-                    cond: b!(Expr::Literal(Int(1))),
-                    then: vec![Statement::Expr(Expr::Literal(Int(1)))],
-                    or: Some(b!(ElseType::Else(vec![Statement::Expr(Expr::Literal(
-                        Int(0)
-                    ))])))
-                })),
-                Some(b!(Expr::Literal(Int(9))))
-            )),
-            then: vec![Statement::Expr(Expr::Op(
-                Eq,
-                b!(Expr::Identifier("a".into())),
-                Some(b!(Expr::Literal(Int(4))))
-            ))],
-            or: Some(b!(ElseType::If(If {
-                cond: b!(Expr::Literal(Int(1))),
-                then: vec![Statement::Expr(Expr::Op(
-                    Eq,
-                    b!(Expr::Identifier("a".into())),
-                    Some(b!(Expr::Literal(Int(5))))
-                ))],
-                or: Some(b!(ElseType::Else(vec![])))
-            })))
-        }))
-    );
-
-    assert_eq!(parser.skip_token(TokenKind::Newline), true);
-
-    assert_eq!(
-        parser.parse_expr(),
-        Some(Expr::Op(
-            CaretEq,
-            b!(Expr::Identifier("amul".into())),
-            Some(b!(Expr::Op(
-                Caret,
-                b!(Expr::Op(
-                    Plus,
-                    b!(Expr::Literal(Int(4))),
-                    Some(b!(Expr::Op(
-                        Star,
-                        b!(Expr::Literal(Int(93))),
-                        Some(b!(Expr::Op(
-                            Slash,
-                            b!(Expr::Op(
-                                Shl,
-                                b!(Expr::Literal(Int(1))),
-                                Some(b!(Expr::Literal(Int(3))))
-                            )),
-                            Some(b!(Expr::Literal(Float(1.44))))
-                        )))
-                    )))
-                )),
-                Some(b!(Expr::Identifier("bhatura".into())))
-            )))
-        ))
-    );
-
-    assert_eq!(parser.skip_token(TokenKind::Newline), true);
-
-    assert_eq!(
-        parser.parse_expr(),
-        Some(Expr::Op(
-            Eq,
-            b!(Expr::Identifier("stove".into())),
-            Some(b!(Expr::Op(
-                Plus,
-                b!(Expr::Block(vec![Statement::Expr(Expr::Literal(Int(44)))])),
-                Some(b!(Expr::Identifier("amul".into())))
-            )))
-        ))
-    );
-}

src/parser/literal.rs

@@ -1,121 +0,0 @@
-use super::Parser;
-use crate::lexer::{
-    TokenKind,
-    TokenLiteral,
-    TokenSymbol,
-};
-
-impl<'a> Parser<'a> {
-    /// int ::= digit { digit }
-    pub(super) fn parse_int(&mut self) -> Option<i32> {
-        let val = self.next_token().val;
-        let mut integer: i32 = 0;
-        let error = || {
-            self.error(&format!(
-                "integer values must be in range [{}, {}]",
-                i32::MIN,
-                i32::MAX
-            ))
-        };
-
-        for c in val.chars() {
-            // c is always ['0'..='9']
-            let d = c.to_digit(10)?;
-
-            match integer.checked_mul(10) {
-                Some(m) => integer = m,
-                None => {
-                    error();
-                    return None;
-                }
-            }
-
-            match integer.checked_add(d as i32) {
-                Some(a) => integer = a,
-                None => {
-                    error();
-                    return None;
-                }
-            }
-        }
-
-        Some(integer)
-    }
-
-    // didnt use parse() because i wanted to do this myself for some reason
-    /// f32 can be NaN and inf as well
-    /// float ::= int [ "." { digit } ] [ "e" { digit } ]
-    pub(super) fn parse_float(&mut self) -> Option<f32> {
-        let token = self.next_token();
-        let mut chars = token.val.chars();
-        let mut float: f32 = 0.0;
-        let mut fraction: f32 = 0.0;
-        let mut prec: i32 = 0;
-        let mut exp: i32 = 0;
-        let mut decimal: bool = false;
-
-        // lexer takes care of multiple decimals and non digit characters
-        for c in chars.by_ref() {
-            match c {
-                '.' => decimal = true,
-                'e' | 'E' => {
-                    // lexer takes care that decimal doesnt come after e
-                    let s;
-                    match self.peek_token().kind {
-                        TokenKind::Symbol(TokenSymbol::Minus) => {
-                            s = -1;
-                            self.next_token();
-                        }
-                        TokenKind::Symbol(TokenSymbol::Plus) => {
-                            s = 1;
-                            self.next_token();
-                        }
-                        _ => s = 1,
-                    }
-
-                    if self.peek_token().kind != TokenKind::Literal(TokenLiteral::Int) {
-                        break;
-                    }
-
-                    exp = self.parse_int()? * s;
-                    break;
-                }
-                _ => {
-                    // c is always ['0'..='9']
-                    let d = c.to_digit(10)? as f32;
-                    if decimal {
-                        fraction *= 10.0;
-                        fraction += d;
-                        prec += 1;
-                    } else {
-                        float *= 10.0;
-                        float += d;
-                    }
-                }
-            }
-        }
-
-        fraction /= 10f32.powi(prec);
-        float += fraction;
-        float *= 10f32.powi(exp);
-
-        Some(float)
-    }
-
-    /// char ::= "'" letter "'"
-    pub(super) fn parse_char(&mut self) -> Option<char> {
-        // the lexer ensures that the 0th and 2nd characters are both '
-        self.next_token().val.chars().nth(1)
-    }
-}
-
-#[test]
-fn test_parse_literals() {
-    let mut parser = Parser::new("4524 3123.15e4 9e2 9083482.429455 'c' 3331.13.1");
-    assert_eq!(parser.parse_int(), Some(4524));
-    assert_eq!(parser.parse_float(), Some(3123.15e4));
-    assert_eq!(parser.parse_float(), Some(9e2));
-    assert_eq!(parser.parse_float(), Some(9083482.429455));
-    assert_eq!(parser.parse_char(), Some('c'));
-    assert_eq!(parser.next_token().kind, TokenKind::Invalid);
-}

src/parser/mod.rs

@@ -1,156 +0,0 @@
-//! A naive parser just to get started
-//!
-//! Can only parse module, class and function declaration now along with let statements
-
-mod entity;
-mod expr;
-mod literal;
-mod statement;
-
-use crate::ast::{
-    Parent,
-    Ty,
-};
-use crate::lexer::{
-    Lexer,
-    Token,
-    TokenKeyword,
-    TokenKind,
-    TokenSymbol,
-};
-use std::rc::Rc;
-
-pub struct Parser<'a> {
-    pub lexer: Lexer<'a>,
-}
-
-impl<'a> Parser<'a> {
-    /// Creates a new [`Parser`] instance.
-    pub fn new(contents: &'a str) -> Parser<'a> {
-        Parser {
-            lexer: Lexer::new(contents),
-        }
-    }
-
-    #[inline]
-    fn error(&self, message: &str) {
-        eprintln!(
-            "Parser: {}, at \"{}:{}\"",
-            message, self.lexer.line, self.lexer.col
-        );
-    }
-
-    #[inline]
-    fn error_expected(&self, expected: &str, found: &str) {
-        self.error(&format!("expected {}, found {}", expected, found));
-    }
-
-    #[inline]
-    fn error_expected_peek(&mut self, expected: &str) {
-        let found = &Rc::clone(&self.peek_token().val);
-        self.error_expected(expected, found);
-    }
-
-    #[inline]
-    fn next_token(&mut self) -> Token {
-        let t = self.lexer.next_token();
-        println!("{:?}", t);
-        t
-    }
-
-    #[inline]
-    fn peek_token(&mut self) -> &Token {
-        return self.lexer.peek_token();
-    }
-
-    /// newline ::= "}\n"
-    fn trim_newlines(&mut self) {
-        while self.peek_token().kind == TokenKind::Newline {
-            self.next_token();
-        }
-    }
-
-    fn skip_token(&mut self, kind: TokenKind) -> bool {
-        if self.peek_token().kind == kind {
-            self.next_token();
-            return true;
-        }
-
-        false
-    }
-
-    fn check_newline_or_tok(&mut self, token: TokenKind) -> bool {
-        match self.peek_token().kind {
-            TokenKind::Newline => true,
-            d if d == token => true,
-            _ => false,
-        }
-    }
-
-    /// ty ::= "int" | "float" | "char"
-    fn parse_ty(&mut self) -> Option<Ty> {
-        let ty: Ty;
-
-        if let TokenKind::Keyword(keyword) = &self.peek_token().kind {
-            ty = match keyword {
-                TokenKeyword::Int => Ty::Int,
-                TokenKeyword::Char => Ty::Char,
-                TokenKeyword::Float => Ty::Float,
-                _ => {
-                    self.error_expected_peek("ty");
-                    return None;
-                }
-            };
-        } else {
-            self.error_expected_peek("ty");
-            return None;
-        }
-        self.next_token();
-        Some(ty)
-    }
-
-    /// ident ::= ( letter | "_" ) { letter | digit | "_" }
-    fn parse_ident(&mut self) -> Option<Rc<str>> {
-        if self.peek_token().kind != TokenKind::Identifier {
-            self.error_expected_peek("identifier");
-            return None;
-        }
-
-        Some(Rc::clone(&self.next_token().val))
-    }
-
-    /// identWithTy ::= letter ":" ty
-    fn parse_ident_with_ty(&mut self) -> Option<(Rc<str>, Ty)> {
-        let ident = self.parse_ident()?;
-
-        if !self.skip_token(TokenKind::Symbol(TokenSymbol::Colon)) {
-            self.error_expected_peek(":");
-            return None;
-        }
-
-        Some((ident, self.parse_ty()?))
-    }
-
-    /// Returns an [`Entity`] vector after parsing
-    ///
-    /// parent ::= { entity }
-    /// [`Entity`]: crate::ast::Entity
-    pub fn parse(&mut self) -> Option<Parent> {
-        let mut parent = vec![];
-
-        loop {
-            match self.peek_token().kind {
-                TokenKind::Newline => self.trim_newlines(),
-                TokenKind::Eof => break,
-                _ => {
-                    parent.push(self.parse_entity()?);
-                    if !self.check_newline_or_tok(TokenKind::Eof) {
-                        self.error_expected_peek("newline or end of file");
-                        return None;
-                    }
-                }
-            }
-        }
-        Some(parent)
-    }
-}

src/parser/statement.rs

@@ -1,91 +0,0 @@
-use super::Parser;
-use crate::ast::*;
-use crate::lexer::{
-    TokenKeyword,
-    TokenKind,
-    TokenSymbol,
-};
-
-impl<'a> Parser<'a> {
-    /// statement ::= static | let | expr
-    pub(super) fn parse_statement(&mut self) -> Option<Statement> {
-        use TokenKeyword::*;
-        println!("STMT");
-
-        Some(match self.peek_token().kind {
-            TokenKind::Keyword(Static) => Statement::Static(self.parse_static()?),
-            TokenKind::Keyword(Let) => Statement::Let(self.parse_let()?),
-            _ => Statement::Expr(self.parse_expr()?),
-        })
-    }
-
-    /// static ::="static" let
-    pub(super) fn parse_static(&mut self) -> Option<Let> {
-        self.next_token();
-
-        if self.peek_token().kind != TokenKind::Keyword(TokenKeyword::Let) {
-            self.error_expected_peek("let");
-            return None;
-        }
-
-        self.parse_let()
-    }
-
-    /// let ::= "let" identWithTy "=" expr
-    pub(super) fn parse_let(&mut self) -> Option<Let> {
-        self.next_token();
-
-        let (name, ty) = self.parse_ident_with_ty()?;
-
-        let expr = if self.skip_token(TokenKind::Symbol(TokenSymbol::Eq)) {
-            self.parse_expr()
-        } else if self.peek_token().kind == TokenKind::Newline {
-            None
-        } else {
-            self.error_expected_peek("= or newline");
-            return None;
-        };
-
-        Some(Let { name, ty, expr })
-    }
-}
-
-#[test]
-fn test_parse_let() {
-    use Literal::*;
-
-    let mut parser = Parser::new(
-        r#"static let test01: int = 4
-           let test02: char = '6'
-           static let test03: float
-           let test04 = 9"#,
-    );
-    assert_eq!(
-        parser.parse_static(),
-        Some(Let {
-            name: "test01".into(),
-            ty: Ty::Int,
-            expr: Some(Expr::Literal(Int(4)))
-        })
-    );
-    assert_eq!(parser.skip_token(TokenKind::Newline), true);
-    assert_eq!(
-        parser.parse_let(),
-        Some(Let {
-            name: "test02".into(),
-            ty: Ty::Char,
-            expr: Some(Expr::Literal(Char('6')))
-        })
-    );
-    assert_eq!(parser.skip_token(TokenKind::Newline), true);
-    assert_eq!(
-        parser.parse_static(),
-        Some(Let {
-            name: "test03".into(),
-            ty: Ty::Float,
-            expr: None
-        })
-    );
-    assert_eq!(parser.skip_token(TokenKind::Newline), true);
-    assert_eq!(parser.parse_let(), None);
-}