Core: Factor + start defer

core_ast.cpp

@@ -177,6 +177,13 @@ ast_return(Token *pos, Ast_Expr *expr) {
     return result;
 }
 
+CORE_Static Ast_Defer *
+ast_defer(Token *pos, Ast_Scope *scope) {
+    Ast_Defer *result = ast_new(Ast_Defer, AST_DEFER, pos, AST_STMT);
+    result->scope = scope;
+    return result;
+}
+
 CORE_Static Ast_Goto *
 ast_goto(Token *pos, Intern_String label) {
     Ast_Goto *result = ast_new(Ast_Goto, AST_GOTO, pos, AST_STMT);

core_compiler.cpp

@@ -67,8 +67,9 @@ for i in meta.token_simple_expr:
     pctx->keyword_for = pctx->intern("for"_s);
     pctx->keyword_enum = pctx->intern("enum"_s);
     pctx->keyword_goto = pctx->intern("goto"_s);
+    pctx->keyword_defer = pctx->intern("defer"_s);
     pctx->interns.first_keyword = pctx->keyword_struct.str;
-    pctx->interns.last_keyword = pctx->keyword_goto.str;
+    pctx->interns.last_keyword = pctx->keyword_defer.str;
     pctx->intern_typeof = pctx->intern("typeof"_s);
     pctx->intern_sizeof = pctx->intern("sizeof"_s);
     pctx->intern_len = pctx->intern("Len"_s);

core_compiler.h

@@ -108,6 +108,7 @@ for i in meta.interns: print(f'Intern_String intern_{i.lower()};')
     Intern_String keyword_for;
     Intern_String keyword_enum;
     Intern_String keyword_goto;
+    Intern_String keyword_defer;
     Intern_String intern_typeof;
     Intern_String intern_sizeof;
     Intern_String intern_len;

core_compiler_interface.hpp

@@ -334,6 +334,7 @@ enum Ast_Kind : uint32_t {
     AST_TYPE_OF,
     AST_VARGS_LAMBDA_PARAM,
 
+    AST_DEFER,
     AST_LABEL,
     AST_GOTO,
     AST_SWITCH,
@@ -535,6 +536,10 @@ struct Ast_Goto : Ast {
     Intern_String label;
 };
 
+struct Ast_Defer : Ast {
+    Ast_Scope *scope;
+};
+
 struct Ast_For : Ast {
     Ast_Expr *init;
     Ast_Expr *cond;

core_parsing.cpp

@@ -271,38 +271,33 @@ parse_optional_type() {
     return result;
 }
 
-CORE_Static Ast_Scope *
+CORE_Static Ast_Scope *parse_stmt_scope(Ast_Scope *scope_defined_outside = 0, bool empty_scope_is_error = true);
-parse_stmt_scope(Ast_Scope *scope_defined_outside = 0) {
-    Ast_Scope *scope = scope_defined_outside;
 
-    if (token_expect(OPEN_SCOPE)) { // @todo: Fix error message here, it doesn't show proper token context
+CORE_Static Ast *
-        Token *token_block = token_get();
+parse_stmt() {
-
-        Scoped_Arena scratch(pctx->scratch);
-        if (!scope_defined_outside) scope = begin_stmt_scope(scratch.arena, token_block);
-        do {
     Token *token = token_get();
+    Scoped_Arena scratch(pctx->scratch);
 
     if (token_match_keyword(pctx->keyword_return)) {
         Ast_Expr *expr = 0;
         if (!token_is_scope()) expr = parse_expr();
-                scope->stmts.add(ast_return(token, expr));
+        return ast_return(token, expr);
     }
 
     else if (token_match_keyword(pctx->keyword_continue)) {
-                scope->stmts.add(ast_continue(token));
+        return ast_continue(token);
     }
 
     else if (token_match_keyword(pctx->intern_compiler_breakpoint)) {
-                scope->stmts.add(ast_compiler_breakpoint(token));
+        return ast_compiler_breakpoint(token);
     }
 
     else if (token_match_keyword(pctx->keyword_break)) {
-                scope->stmts.add(ast_break(token));
+        return ast_break(token);
     }
 
     else if (token_match_keyword(pctx->keyword_pass)) {
-                scope->stmts.add(ast_pass(token));
+        return ast_pass(token);
     }
 
     else if (token_match_keyword(pctx->keyword_switch)) {
@@ -333,7 +328,7 @@ parse_stmt_scope(Ast_Scope *scope_defined_outside = 0) {
         token_expect(CLOSE_SCOPE);
         result->cases = result->cases.tight_copy(pctx->perm);
 
-                scope->stmts.add(result);
+        return result;
     }
 
     else if (token_match_keyword(pctx->keyword_assert)) {
@@ -345,7 +340,7 @@ parse_stmt_scope(Ast_Scope *scope_defined_outside = 0) {
             message = t->intern_val;
         }
         token_expect(TK_CloseParen);
-                scope->stmts.add(ast_runtime_assert(token, expr, message));
+        return ast_runtime_assert(token, expr, message);
     }
 
     else if (token_match_pound(pctx->keyword_assert)) {
@@ -357,7 +352,7 @@ parse_stmt_scope(Ast_Scope *scope_defined_outside = 0) {
             message = t->intern_val;
         }
         token_expect(TK_CloseParen);
-                scope->stmts.add(ast_constant_assert(token, expr, message));
+        return ast_constant_assert(token, expr, message);
     }
 
     else if (token_match_keyword(pctx->keyword_for)) {
@@ -383,7 +378,7 @@ parse_stmt_scope(Ast_Scope *scope_defined_outside = 0) {
 
         parse_stmt_scope(for_scope);
         finalize_stmt_scope(for_scope);
-                scope->stmts.add(ast_for(token, init, cond, iter, for_scope));
+        return ast_for(token, init, cond, iter, for_scope);
     }
 
     else if (token_match_keyword(pctx->keyword_if)) {
@@ -419,14 +414,17 @@ parse_stmt_scope(Ast_Scope *scope_defined_outside = 0) {
                 break;
             }
         }
-                Ast_If *result_if = ast_if(token, if_nodes);
+        return ast_if(token, if_nodes);
-                scope->stmts.add(result_if);
+    }
+
+    else if (token_match_keyword(pctx->keyword_defer)) {
+        Ast_Scope *s = parse_stmt_scope();
+        return ast_defer(token, s);
     }
 
     else if (token_match_keyword(pctx->keyword_goto)) {
         Token *ident = token_expect(TK_Identifier);
-                Ast_Goto *result = ast_goto(token, ident->intern_val);
+        return ast_goto(token, ident->intern_val);
-                scope->stmts.add(result);
     }
 
     // Label
@@ -441,7 +439,7 @@ parse_stmt_scope(Ast_Scope *scope_defined_outside = 0) {
 
         Ast_Label *result = ast_label(token, ident->intern_val, s, enable_goto);
         if (breakpoint) set_flag(result->flags, AST_COMPILER_BREAKPOINT);
-                scope->stmts.add(result);
+        return result;
     }
 
     // Var unpack
@@ -456,7 +454,7 @@ parse_stmt_scope(Ast_Scope *scope_defined_outside = 0) {
         token_expect(TK_ColonAssign);
         Ast_Expr *expr = parse_expr();
         Ast_Var_Unpack *vars = ast_var_unpack(token, decls, expr);
-                scope->stmts.add(vars);
+        return vars;
     }
 
     // Declaration or init stmt
@@ -469,20 +467,32 @@ parse_stmt_scope(Ast_Scope *scope_defined_outside = 0) {
             result = parse_expr();
             result = parse_init_stmt((Ast_Expr *)result);
         }
-
         if (result) {
             result->flags = set_flag(result->flags, AST_STMT);
-                    scope->stmts.add(result);
+            return result;
         }
         else {
             compiler_error(token, "Unexpected token [%s] while parsing statement", name(token->kind));
+            return 0;
         }
     }
+}
+
+CORE_Static Ast_Scope *
+parse_stmt_scope(Ast_Scope *scope_defined_outside, bool empty_scope_is_error) {
+    Scoped_Arena scratch(pctx->scratch);
+    Ast_Scope *scope = scope_defined_outside;
+    if (!scope_defined_outside) scope = begin_stmt_scope(scratch.arena, token_get());
+
+    if (token_expect(OPEN_SCOPE)) { // @todo: Fix error message here, it doesn't show proper token context
+        do {
+            Ast *stmt = parse_stmt();
+            scope->stmts.add(stmt);
         } while (token_match(SAME_SCOPE));
         token_expect(CLOSE_SCOPE);
+    }
 
     if (!scope_defined_outside) finalize_stmt_scope(scope);
-    }
     return scope;
 }
 

meta.py

@@ -116,6 +116,7 @@ keywords = [
   "for",
   "enum",
   "goto",
+  "defer",
 ]
 
 interns = [