From 816aebda014fecaf68a99d52ed93c409de703429 Mon Sep 17 00:00:00 2001
From: janis <janis@nirgendwo.xyz>
Date: Tue, 30 Sep 2025 17:29:38 +0200
Subject: [PATCH] try out pomelo parser

---
 crates/parser/Cargo.toml |   5 +-
 crates/parser/src/lib.rs | 104 +++++++++++++++++++++++++++++++++++++--
 2 files changed, 104 insertions(+), 5 deletions(-)

diff --git a/crates/parser/Cargo.toml b/crates/parser/Cargo.toml
index 4db7793..c93d5c5 100644
--- a/crates/parser/Cargo.toml
+++ b/crates/parser/Cargo.toml
@@ -11,4 +11,7 @@ thiserror = { workspace = true }
 itertools = { workspace = true }
 internment = "0.8.6"
 
-lexer = { path = "../lexer", version = "0.1.0" }
\ No newline at end of file
+lexer = { path = "../lexer", version = "0.1.0" }
+
+logos = "0.15"
+pomelo = "0.2"
\ No newline at end of file
diff --git a/crates/parser/src/lib.rs b/crates/parser/src/lib.rs
index e6ef52b..885462d 100644
--- a/crates/parser/src/lib.rs
+++ b/crates/parser/src/lib.rs
@@ -3,6 +3,8 @@ use lexer::{
     Consuming, ReborrowingConsumingIterator, ReborrowingIterator, ReborrowingPeekingIterator,
     Token, TokenConsumer, TokenItem, TokenItemIterator,
 };
+use logos::Logos;
+use pomelo::pomelo;
 use thiserror::Error;
 
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
@@ -87,10 +89,7 @@ pub enum AstNode {
         name: String,
         param_type: Type,
     },
-    FunctionDecl {
-        proto: Index,
-        body: Index,
-    },
+    FunctionDecl(FunctionDecl),
     Block {
         statements: Vec<Index>,
         expr: Option<Index>,
@@ -274,6 +273,103 @@ impl Ast {
     pub fn new() -> Self {
         Self::default()
     }
+    pub fn push(&mut self, node: AstNode) -> Index {
+        let index = self.nodes.len() as u32;
+        self.nodes.push(node);
+        Index(index)
+    }
+}
+
+#[derive(Debug)]
+struct FunctionDecl {
+    name: String,
+    return_type: Type,
+    parameter_list: Option<ParameterList>,
+    body: Index,
+}
+
+#[derive(Debug)]
+struct Parameter {
+    name: String,
+    param_type: Type,
+}
+
+#[derive(Debug)]
+struct ParameterList {
+    parameters: Vec<Index>,
+}
+
+#[derive(Debug)]
+struct ExtraToken<'a> {
+    lexeme: &'a str,
+    offset: u32,
+}
+
+pomelo! {
+    %include {
+        use super::AstNode;
+        use super::{
+            Parameter, Ast, ParameterList, FunctionDecl, Type, InnerType,
+            FloatType, ExtraToken, Index,
+        };
+    };
+    %extra_argument Ast;
+    %parser pub struct Parser<'a>{};
+    %extra_token (&'a str, u32);
+    %type fn_decl FunctionDecl;
+    %type parameter Parameter;
+    %type parameter_list ParameterList;
+    %type typ Type;
+    %type return_type Type;
+    %type block Index;
+
+    file ::= decl_list?;
+    decl_list ::= decl;
+    decl_list ::= decl_list decl;
+
+    typ ::= Bool { internment::Intern::new(InnerType::Bool) };
+    typ ::= I8 { internment::Intern::new(InnerType::Int { signed: true, bits: 8 }) };
+    typ ::= I16 { internment::Intern::new(InnerType::Int { signed: true, bits: 16 }) };
+    typ ::= I32 { internment::Intern::new(InnerType::Int { signed: true, bits: 32 }) };
+    typ ::= I64 { internment::Intern::new(InnerType::Int { signed: true, bits: 64 }) };
+    typ ::= U8 { internment::Intern::new(InnerType::Int { signed: false, bits: 8 }) };
+    typ ::= U16 { internment::Intern::new(InnerType::Int { signed: false, bits: 16 }) };
+    typ ::= U32 { internment::Intern::new(InnerType::Int { signed: false, bits: 32 }) };
+    typ ::= U64 { internment::Intern::new(InnerType::Int { signed: false, bits: 64 }) };
+    typ ::= F32 { internment::Intern::new(InnerType::Float { float_type: FloatType::F32 }) };
+    typ ::= F64 { internment::Intern::new(InnerType::Float { float_type: FloatType::F64 }) };
+    typ ::= Bang { internment::Intern::new(InnerType::Bottom) };
+    typ ::= LParen RParen { internment::Intern::new(InnerType::Unit) };
+
+    return_type ::= Arrow typ(return_type) { return_type };
+    block ::= LBrace RBrace { extra.push(AstNode::Block { statements: vec![], expr: None }) };
+    parameter ::= Ident(name) Colon typ(param_type) {
+        Parameter { name: name.0.to_string(), param_type }
+    };
+    parameter_list ::= parameter(p) {
+        let idx = extra.push(AstNode::Parameter { name: p.name, param_type: p.param_type });
+        ParameterList { parameters: vec![idx] }
+    };
+    parameter_list ::= parameter_list(pl) Comma parameter(p) {
+        let idx = extra.push(AstNode::Parameter { name: p.name, param_type: p.param_type });
+        let mut parameters = pl.parameters;
+        parameters.push(idx);
+        ParameterList { parameters }
+    };
+    parameter_list ::= parameter_list(pl) Comma {
+        pl
+    };
+
+    decl ::= fn_decl(f) { extra.nodes.push(AstNode::FunctionDecl(f)); };
+    fn_decl ::= Fn Ident(name) LParen parameter_list?(parameters) RParen return_type(rtype) block(body) {
+        let name = name.0.to_string();
+        FunctionDecl {
+            name,
+            return_type: rtype,
+            parameter_list: parameters,
+            body,
+        }
+    };
 }
 
 #[cfg(test)]