Add `where` clauses to `struct` and `union`

1 files changed, 50 insertions, 17 deletions

diff --git a/src/parser.cpp b/src/parser.cpp
index 123e1fcee..204ff3984 100644
--- a/src/parser.cpp
+++ b/src/parser.cpp
@@ -349,10 +349,12 @@ Ast *clone_ast(Ast *node) {
 		n->StructType.fields = clone_ast_array(n->StructType.fields);
 		n->StructType.polymorphic_params = clone_ast(n->StructType.polymorphic_params);
 		n->StructType.align  = clone_ast(n->StructType.align);
+		n->StructType.where_clauses  = clone_ast_array(n->StructType.where_clauses);
 		break;
 	case Ast_UnionType:
 		n->UnionType.variants = clone_ast_array(n->UnionType.variants);
 		n->UnionType.polymorphic_params = clone_ast(n->UnionType.polymorphic_params);
+		n->UnionType.where_clauses = clone_ast_array(n->UnionType.where_clauses);
 		break;
 	case Ast_EnumType:
 		n->EnumType.base_type = clone_ast(n->EnumType.base_type);
@@ -921,7 +923,8 @@ Ast *ast_dynamic_array_type(AstFile *f, Token token, Ast *elem) {
 
 Ast *ast_struct_type(AstFile *f, Token token, Array<Ast *> fields, isize field_count,
                      Ast *polymorphic_params, bool is_packed, bool is_raw_union,
-                     Ast *align) {
+                     Ast *align,
+                     Token where_token, Array<Ast *> const &where_clauses) {
 	Ast *result = alloc_ast_node(f, Ast_StructType);
 	result->StructType.token              = token;
 	result->StructType.fields             = fields;
@@ -930,17 +933,22 @@ Ast *ast_struct_type(AstFile *f, Token token, Array<Ast *> fields, isize field_c
 	result->StructType.is_packed          = is_packed;
 	result->StructType.is_raw_union       = is_raw_union;
 	result->StructType.align              = align;
+	result->StructType.where_token        = where_token;
+	result->StructType.where_clauses      = where_clauses;
 	return result;
 }
 
 
-Ast *ast_union_type(AstFile *f, Token token, Array<Ast *> variants, Ast *polymorphic_params, Ast *align, bool no_nil) {
+Ast *ast_union_type(AstFile *f, Token token, Array<Ast *> variants, Ast *polymorphic_params, Ast *align, bool no_nil,
+                    Token where_token, Array<Ast *> const &where_clauses) {
 	Ast *result = alloc_ast_node(f, Ast_UnionType);
 	result->UnionType.token              = token;
 	result->UnionType.variants           = variants;
 	result->UnionType.polymorphic_params = polymorphic_params;
 	result->UnionType.align              = align;
 	result->UnionType.no_nil             = no_nil;
+	result->UnionType.where_token        = where_token;
+	result->UnionType.where_clauses      = where_clauses;
 	return result;
 }
 
@@ -2020,6 +2028,18 @@ Ast *parse_operand(AstFile *f, bool lhs) {
 			syntax_error(token, "'#raw_union' cannot also be '#packed'");
 		}
 
+		Token where_token = {};
+		Array<Ast *> where_clauses = {};
+
+		if (f->curr_token.kind == Token_where) {
+			where_token = expect_token(f, Token_where);
+			isize prev_level = f->expr_level;
+			f->expr_level = -1;
+			where_clauses = parse_rhs_expr_list(f);
+			f->expr_level = prev_level;
+		}
+
+
 		Token open = expect_token_after(f, Token_OpenBrace, "struct");
 
 		isize    name_count = 0;
@@ -2032,7 +2052,7 @@ Ast *parse_operand(AstFile *f, bool lhs) {
 			decls = fields->FieldList.list;
 		}
 
-		return ast_struct_type(f, token, decls, name_count, polymorphic_params, is_packed, is_raw_union, align);
+		return ast_struct_type(f, token, decls, name_count, polymorphic_params, is_packed, is_raw_union, align, where_token, where_clauses);
 	} break;
 
 	case Token_union: {
@@ -2073,6 +2093,18 @@ Ast *parse_operand(AstFile *f, bool lhs) {
 			}
 		}
 
+		Token where_token = {};
+		Array<Ast *> where_clauses = {};
+
+		if (f->curr_token.kind == Token_where) {
+			where_token = expect_token(f, Token_where);
+			isize prev_level = f->expr_level;
+			f->expr_level = -1;
+			where_clauses = parse_rhs_expr_list(f);
+			f->expr_level = prev_level;
+		}
+
+
 		Token open = expect_token_after(f, Token_OpenBrace, "union");
 
 		while (f->curr_token.kind != Token_CloseBrace &&
@@ -2088,7 +2120,7 @@ Ast *parse_operand(AstFile *f, bool lhs) {
 
 		Token close = expect_token(f, Token_CloseBrace);
 
-		return ast_union_type(f, token, variants, polymorphic_params, align, no_nil);
+		return ast_union_type(f, token, variants, polymorphic_params, align, no_nil, where_token, where_clauses);
 	} break;
 
 	case Token_enum: {
@@ -4424,19 +4456,6 @@ bool determine_path_from_string(gbMutex *file_mutex, Ast *node, String base_dir,
 	}
 
 
-	if (is_package_name_reserved(file_str)) {
-		*path = file_str;
-		return true;
-	}
-
-	if (file_mutex) gb_mutex_lock(file_mutex);
-	defer (if (file_mutex) gb_mutex_unlock(file_mutex));
-
-
-	if (node->kind == Ast_ForeignImportDecl) {
-		node->ForeignImportDecl.collection_name = collection_name;
-	}
-
 	if (collection_name.len > 0) {
 		if (collection_name == "system") {
 			if (node->kind != Ast_ForeignImportDecl) {
@@ -4467,6 +4486,20 @@ bool determine_path_from_string(gbMutex *file_mutex, Ast *node, String base_dir,
 #endif
 	}
 
+
+	if (is_package_name_reserved(file_str)) {
+		*path = file_str;
+		return true;
+	}
+
+	if (file_mutex) gb_mutex_lock(file_mutex);
+	defer (if (file_mutex) gb_mutex_unlock(file_mutex));
+
+
+	if (node->kind == Ast_ForeignImportDecl) {
+		node->ForeignImportDecl.collection_name = collection_name;
+	}
+
 	if (has_windows_drive) {
 		*path = file_str;
 	} else {