From 90ecde89c9cb14408513129354700c2b14fa82d1 Mon Sep 17 00:00:00 2001
From: greg <greg.shuflin@protonmail.com>
Date: Thu, 12 Jul 2018 02:07:52 -0700
Subject: [PATCH] Mutable types

---
 schala-lang/src/ast.rs          |  6 +++++-
 schala-lang/src/parsing.rs      | 34 +++++++++++++++++++++------------
 schala-lang/src/reduced_ast.rs  |  2 +-
 schala-lang/src/symbol_table.rs |  2 +-
 4 files changed, 29 insertions(+), 15 deletions(-)

diff --git a/schala-lang/src/ast.rs b/schala-lang/src/ast.rs
index 315a216..191997c 100644
--- a/schala-lang/src/ast.rs
+++ b/schala-lang/src/ast.rs
@@ -21,7 +21,11 @@ pub type FormalParam = (ParamName, Option<TypeName>);
 pub enum Declaration {
   FuncSig(Signature),
   FuncDecl(Signature, Block),
-  TypeDecl(TypeSingletonName, TypeBody), //should have TypeSingletonName in it
+  TypeDecl {
+    name: TypeSingletonName,
+    body: TypeBody,
+    mutable: bool
+  },
   TypeAlias(Rc<String>, Rc<String>), //should have TypeSingletonName in it, or maybe just String, not sure
   Binding {
     name: Rc<String>,
diff --git a/schala-lang/src/parsing.rs b/schala-lang/src/parsing.rs
index bdb3762..6a2546f 100644
--- a/schala-lang/src/parsing.rs
+++ b/schala-lang/src/parsing.rs
@@ -316,14 +316,16 @@ impl Parser {
     if let Keyword(Alias) = self.peek() {
       self.type_alias()
     } else {
-      if let Keyword(Mut) = self.peek() {
+      let mutable = if let Keyword(Mut) = self.peek() {
         self.next();
-        //TODO make this part of the type
-      }
+        true
+      } else {
+        false
+      };
       let name = self.type_singleton_name()?;
       expect!(self, Operator(ref c) if **c == "=");
       let body = self.type_body()?;
-      Ok(Declaration::TypeDecl(name, body))
+      Ok(Declaration::TypeDecl { name, body, mutable})
     }
   });
 
@@ -1167,24 +1169,32 @@ fn a(x) {
 
   #[test]
   fn parsing_types() {
-    parse_test!("type Yolo = Yolo", AST(vec![Declaration(TypeDecl(tys!("Yolo"), TypeBody(vec![UnitStruct(rc!(Yolo))])))]));
+    parse_test!("type Yolo = Yolo", AST(vec![Declaration(TypeDecl { name: tys!("Yolo"), body: TypeBody(vec![UnitStruct(rc!(Yolo))]), mutable: false} )]));
+    parse_test!("type mut Yolo = Yolo", AST(vec![Declaration(TypeDecl { name: tys!("Yolo"), body: TypeBody(vec![UnitStruct(rc!(Yolo))]), mutable: true} )]));
     parse_test!("type alias Sex = Drugs", AST(vec![Declaration(TypeAlias(rc!(Sex), rc!(Drugs)))]));
     parse_test!("type Sanchez = Miguel | Alejandro(Int, Option<a>) | Esperanza { a: Int, b: String }",
-      AST(vec![Declaration(TypeDecl(tys!("Sanchez"), TypeBody(vec![
+    AST(vec![Declaration(TypeDecl{
+      name: tys!("Sanchez"),
+      body: TypeBody(vec![
         UnitStruct(rc!(Miguel)),
         TupleStruct(rc!(Alejandro), vec![
           Singleton(TypeSingletonName { name: rc!(Int), params: vec![] }),
           Singleton(TypeSingletonName { name: rc!(Option), params: vec![Singleton(TypeSingletonName { name: rc!(a), params: vec![] })] }),
         ]),
         Record(rc!(Esperanza), vec![
-          (rc!(a), Singleton(TypeSingletonName { name: rc!(Int), params: vec![] })),
-          (rc!(b), Singleton(TypeSingletonName { name: rc!(String), params: vec![] })),
-        ])])))]));
+              (rc!(a), Singleton(TypeSingletonName { name: rc!(Int), params: vec![] })),
+              (rc!(b), Singleton(TypeSingletonName { name: rc!(String), params: vec![] })),
+        ])
+      ]),
+      mutable: false
+    })]));
 
     parse_test!("type Jorge<a> = Diego | Kike(a)", AST(vec![
-      Declaration(TypeDecl(
-        TypeSingletonName { name: rc!(Jorge), params: vec![Singleton(TypeSingletonName { name: rc!(a), params: vec![] })] },
-        TypeBody(vec![UnitStruct(rc!(Diego)), TupleStruct(rc!(Kike), vec![Singleton(TypeSingletonName { name: rc!(a), params: vec![] })])]))
+      Declaration(TypeDecl{
+        name: TypeSingletonName { name: rc!(Jorge), params: vec![Singleton(TypeSingletonName { name: rc!(a), params: vec![] })] },
+        body: TypeBody(vec![UnitStruct(rc!(Diego)), TupleStruct(rc!(Kike), vec![Singleton(TypeSingletonName { name: rc!(a), params: vec![] })])]),
+        mutable: false
+      }
     )]));
   }
 
diff --git a/schala-lang/src/reduced_ast.rs b/schala-lang/src/reduced_ast.rs
index 854fb36..5e970b8 100644
--- a/schala-lang/src/reduced_ast.rs
+++ b/schala-lang/src/reduced_ast.rs
@@ -156,7 +156,7 @@ impl Declaration {
           body: statements.iter().map(|stmt| stmt.reduce(symbol_table)).collect(),
         }
       },
-      TypeDecl(_,_) => Stmt::Noop,
+      TypeDecl { .. } => Stmt::Noop,
       _ => Stmt::Expr(Expr::UnimplementedSigilValue)
     }
   }
diff --git a/schala-lang/src/symbol_table.rs b/schala-lang/src/symbol_table.rs
index 431f351..d9ebd56 100644
--- a/schala-lang/src/symbol_table.rs
+++ b/schala-lang/src/symbol_table.rs
@@ -79,7 +79,7 @@ impl SymbolTable {
               Symbol { name: signature.name.clone(), spec }
               );
           },
-          TypeDecl(TypeSingletonName { name, params}, TypeBody(variants)) => {
+          TypeDecl { name: TypeSingletonName { name, params}, body: TypeBody(variants), mutable } => {
             for var in variants {
               match var {
                 Variant::UnitStruct(variant_name) => {