feat: Eliminate any type from Casa

.github/workflows/test-compiler.yml

@@ -14,21 +14,13 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v5
-    - uses: actions/checkout@v5
-      with:
-        ref: main
-        path: main-src
     - name: Download casac release binary
       run: |
         curl --silent --location --fail \
           --output casac-release \
           "https://github.com/frendsick/casa/releases/latest/download/casac"
         chmod +x casac-release
-    - name: Bootstrap stage0 compiler from main
-      run: |
-        cd main-src
-        ../casac-release -L lib casa.casa -o ../casac-main
     - name: Bootstrap stage1 compiler from branch
-      run: ./casac-main -L lib casa.casa -o casac-stage1
+      run: ./casac-release -L lib casa.casa -o casac-stage1
     - name: Run compiler tests
       run: ./tests/test_compiler.sh ./casac-stage1

.github/workflows/test-examples.yml

@@ -14,21 +14,13 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v5
-    - uses: actions/checkout@v5
-      with:
-        ref: main
-        path: main-src
     - name: Download casac release binary
       run: |
         curl --silent --location --fail \
           --output casac-release \
           "https://github.com/frendsick/casa/releases/latest/download/casac"
         chmod +x casac-release
-    - name: Bootstrap stage0 compiler from main
-      run: |
-        cd main-src
-        ../casac-release -L lib casa.casa -o ../casac-main
     - name: Bootstrap stage1 compiler from branch
-      run: ./casac-main -L lib casa.casa -o casac-stage1
+      run: ./casac-release -L lib casa.casa -o casac-stage1
     - name: Test example programs
       run: ./tests/test_examples.sh ./casac-stage1

compiler/common.casa

@@ -725,6 +725,7 @@ struct CasaTrait {
     name:        str
     type_params: List[str]
     methods:     List[TraitMethod]
+    supertraits: List[TraitBound]
     location:    Location
 }
 
@@ -831,7 +832,8 @@ struct Program {
 # Constants
 # ============================================================================
 "_start" = GLOBAL_SCOPE_LABEL
-"any" = ANY_TYPE
+"?" = TYPE_UNKNOWN
+"<missing>" = TYPE_MISSING
 "_" = MATCH_WILDCARD
 "self" = TRAIT_SELF_TYPE
 8 = WORD_SIZE
@@ -966,7 +968,6 @@ fn is_builtin_type typ:str -> bool {
     "str" typ == ||
     "ptr" typ == ||
     "array" typ == ||
-    "any" typ == ||
 }
 
 # ============================================================================
@@ -1057,7 +1058,7 @@ fn signature_matches sig_a:Signature sig_b:Signature -> bool {
     while index sig_a Signature::parameters.length > do
         index sig_a Signature::parameters.get Parameter::typ = type_a
         index sig_b Signature::parameters.get Parameter::typ = type_b
-        if type_a type_b != ANY_TYPE type_a != && ANY_TYPE type_b != && then
+        if type_a type_b != TYPE_UNKNOWN type_a != && TYPE_UNKNOWN type_b != && then
             type_b extract_generic_base = base_b
             type_a extract_generic_base = base_a
             if base_b.is_some type_a base_b.unwrap_or "" == && ! then
@@ -1073,7 +1074,7 @@ fn signature_matches sig_a:Signature sig_b:Signature -> bool {
     while index sig_a Signature::return_types.length > do
         index sig_a Signature::return_types.get = return_a
         index sig_b Signature::return_types.get = return_b
-        if return_a return_b != ANY_TYPE return_a != && ANY_TYPE return_b != && then
+        if return_a return_b != TYPE_UNKNOWN return_a != && TYPE_UNKNOWN return_b != && then
             return_b extract_generic_base = return_base_b
             return_a extract_generic_base = return_base_a
             if return_base_b.is_some return_base_a.is_some && return_base_b.unwrap return_base_a.unwrap == && then
@@ -1090,8 +1091,8 @@ fn signature_matches sig_a:Signature sig_b:Signature -> bool {
                             param_index params_b.get = param_b
                             if
                             param_a param_b !=
-                            ANY_TYPE param_a != &&
-                            ANY_TYPE param_b != &&
+                            TYPE_UNKNOWN param_a != &&
+                            TYPE_UNKNOWN param_b != &&
                             param_a.length 1 != &&
                             param_b.length 1 != &&
                             then
@@ -1493,7 +1494,6 @@ fn symbol_store_new -> SymbolStore {
     "cstr" builtins.add = builtins
     "ptr" builtins.add = builtins
     "array" builtins.add = builtins
-    "any" builtins.add = builtins
 
     builtins
     Map::new(Map[str CasaTrait])

compiler/syntax.casa

@@ -192,7 +192,7 @@ fn parse_type cursor:TokenCursor -> str {
     cursor.peek = peek_opt
     if peek_opt.is_none then
         empty_location "Expected type" ErrorKind::UnexpectedToken raise_error
-        "any" return
+        "" return
     fi
     peek_opt.unwrap = peek
 
@@ -285,6 +285,7 @@ fn get_op_type_cast cursor:TokenCursor -> Op {
     close_token Token::location Location::span Span::offset = close_offset
     close_offset open_offset - 1 + = length
     length open_offset open_token Token::location Location::file make_location = loc
+
     loc cast_type OpValue::TypeCast make_op
 }
 
@@ -868,6 +869,37 @@ fn parse_signature cursor:TokenCursor -> Signature {
 # Bounds whose trait is not registered in the store are silently skipped,
 # matching the pre-extraction behavior of both call sites.
 
+fn collect_trait_methods_into
+    seen:Set[str]
+    result:List[TraitMethod]
+    parser:Parser
+    trait_def:CasaTrait
+-> Set[str] {
+    for ctm_method in trait_def CasaTrait::methods.iter do
+        if ctm_method TraitMethod::name seen.has ! then
+            ctm_method TraitMethod::name seen.add = seen
+            ctm_method result.push
+        fi
+    done
+    for ctm_super in trait_def CasaTrait::supertraits.iter do
+        ctm_super TraitBound::name parser.store.traits.get = ctm_super_opt
+        if ctm_super_opt.is_some then
+            ctm_super_opt.unwrap parser result seen collect_trait_methods_into = seen
+        fi
+    done
+    seen
+}
+# Returns all methods (abstract + default) from `trait_def` and its
+# transitive supertraits, deduplicated by name. The trait's own methods
+# come first; supertrait methods follow in declaration order.
+
+fn collect_trait_methods parser:Parser trait_def:CasaTrait -> List[TraitMethod] {
+    List::new(List[TraitMethod]) = result
+    Set::new(Set[str]) = seen
+    trait_def parser result seen collect_trait_methods_into drop
+    result
+}
+
 fn build_hidden_trait_methods
     parser:Parser
     trait_bounds:Map[str TraitBound]
@@ -891,7 +923,7 @@ fn build_hidden_trait_methods
                     1 += bhtm_sub_index
                 done
             fi
-            for bound_method in bound_trait CasaTrait::methods.iter do
+            for bound_method in bound_trait parser collect_trait_methods.iter do
                 # Skip default methods — only abstract methods need hidden fn ptrs
                 if 0 bound_method TraitMethod::default_ops.length == then
                     f"__trait_{bound_type_var}_{bound_method TraitMethod::name}" = hidden_name
@@ -1288,6 +1320,35 @@ fn parse_trait parser:Parser cursor:TokenCursor -> CasaTrait {
         "trait" cursor parse_simple_type_vars = type_params
     fi
 
+    List::new(List[TraitBound]) = supertraits
+    cursor.peek = colon_opt
+    if colon_opt.is_some ":" colon_opt.unwrap Token::value == && then
+        cursor.pop drop
+        true = parse_super_loop
+        while parse_super_loop do
+            TokenKind::Identifier cursor expect_token_kind = super_token
+            super_token Token::value = super_name
+            super_name parser.store.traits.get = super_def_opt
+            if super_def_opt.is_none then
+                super_token Token::location f"Supertrait `{super_name}` is not defined" ErrorKind::UndefinedName raise_error
+            fi
+            super_token cursor parse_bound_type_args = super_args
+            if super_def_opt.is_some then
+                super_def_opt.unwrap CasaTrait::type_params = super_params
+                if super_args.length super_params.length != then
+                    super_token Token::location f"Supertrait `{super_name}` expects {super_params.length} type argument(s), got {super_args.length}" ErrorKind::Syntax raise_error
+                fi
+            fi
+            super_args super_name TraitBound supertraits.push
+            cursor.peek = plus_opt
+            if plus_opt.is_some "+" plus_opt.unwrap Token::value == && then
+                cursor.pop drop
+            else
+                false = parse_super_loop
+            fi
+        done
+    fi
+
     List::new(List[TraitMethod]) = methods
     "{" cursor expect_token_value drop
 
@@ -1329,7 +1390,7 @@ fn parse_trait parser:Parser cursor:TokenCursor -> CasaTrait {
         fi
     done
 
-    name_token Token::location methods type_params name_token Token::value CasaTrait
+    name_token Token::location supertraits methods type_params name_token Token::value CasaTrait
 }
 
 # ============================================================================