From 205e2d9fd34ac1d6870978848ff6692ff00e9c26 Mon Sep 17 00:00:00 2001
From: Klesti Selimaj <klesti.selimay@icloud.com>
Date: Fri, 8 May 2026 16:48:31 +0200
Subject: [PATCH] generics parsing and AST

---
 parser/src/ast.rs       |  4 ++++
 parser/src/grammar.pest |  8 +++++++-
 parser/src/lib.rs       | 42 +++++++++++++++++++++++++++++------------
 3 files changed, 41 insertions(+), 13 deletions(-)

diff --git a/parser/src/ast.rs b/parser/src/ast.rs
index dc77c0e..8b29051 100644
--- a/parser/src/ast.rs
+++ b/parser/src/ast.rs
@@ -81,6 +81,7 @@ pub enum TopLevelKind {
     },
     StructDecl {
         visibility: Visibility,
+        generics: Generics,
         name: Identifier,
         fields: FieldList,
     },
@@ -94,6 +95,9 @@ pub enum TopLevelKind {
     },
 }
 
+#[derive(Debug, Clone, Serialize)]
+pub struct Generics(pub Vec<(Identifier, Vec<Path>)>);
+
 #[derive(Debug, Clone, Serialize)]
 pub enum Pattern {
     NamedTuple(Path, Vec<Identifier>),
diff --git a/parser/src/grammar.pest b/parser/src/grammar.pest
index 3b7eb05..5d8b892 100644
--- a/parser/src/grammar.pest
+++ b/parser/src/grammar.pest
@@ -52,6 +52,12 @@ export  = { "public" }
 mutable = { "mut" }
 var     = { "var" }
 
+// ======================================================
+// GENERICS
+// ======================================================
+generic  = { identifier ~ (":" ~ static_path ~ ("+" ~ static_path)*)? }
+generics = { "<" ~ (generic ~ ("," ~ generic)*)? ~ ">" }
+
 // ======================================================
 // TYPES
 // ======================================================
@@ -168,7 +174,7 @@ mod_package = {
 // ======================================================
 
 struct_decl = {
-    export? ~ "struct" ~ identifier ~ "{" ~ field_list? ~ "}"
+    export? ~ "struct" ~ identifier ~ generics? ~ "{" ~ field_list? ~ "}"
 }
 
 // ======================================================
diff --git a/parser/src/lib.rs b/parser/src/lib.rs
index 2128993..79886ac 100644
--- a/parser/src/lib.rs
+++ b/parser/src/lib.rs
@@ -223,6 +223,28 @@ impl From<pest::iterators::Pair<'_, Rule>> for ClassConstructor {
     }
 }
 
+impl From<pest::iterators::Pair<'_, Rule>> for Generics {
+    fn from(pair: pest::iterators::Pair<'_, Rule>) -> Self {
+        let rule = pair.as_rule();
+        let inner = pair.clone().into_inner();
+
+        match rule {
+            Rule::generics => Generics(
+                inner
+                    .map(|pair| {
+                        let mut inner = pair.into_inner();
+                        (
+                            Identifier::from(inner.next().unwrap()),
+                            inner.map(Path::from).collect(),
+                        )
+                    })
+                    .collect(),
+            ),
+            _ => unimplemented!("{rule:#?}"),
+        }
+    }
+}
+
 impl From<pest::iterators::Pair<'_, Rule>> for TopLevelKind {
     fn from(pair: pest::iterators::Pair<'_, Rule>) -> Self {
         let rule = pair.as_rule();
@@ -233,18 +255,14 @@ impl From<pest::iterators::Pair<'_, Rule>> for TopLevelKind {
 
             Rule::function_decl => TopLevelKind::FunctionDecl(FunctionDecl::from(pair)),
 
-            Rule::struct_decl => {
-                let visibility = Visibility::from(&mut inner);
-                let name = Identifier::from(inner.next().unwrap());
-                let fields_pair = inner.next().unwrap();
-                let fields = FieldList::from(fields_pair);
-
-                TopLevelKind::StructDecl {
-                    visibility,
-                    name,
-                    fields,
-                }
-            }
+            Rule::struct_decl => TopLevelKind::StructDecl {
+                visibility: Visibility::from(&mut inner),
+                name: Identifier::from(inner.next().unwrap()),
+                generics: consume_rule(&mut inner, Rule::generics)
+                    .map(Generics::from)
+                    .unwrap_or(Generics(Vec::new())),
+                fields: FieldList::from(inner.next().unwrap()),
+            },
 
             Rule::class_decl => TopLevelKind::ClassDecl {
                 visibility: Visibility::from(&mut inner),