Add ast_is() function; use it in symbol.c

1 files changed, 30 insertions, 0 deletions

diff --git a/ast.c b/ast.c
index cbf588a..e64dc9f 100644
--- a/ast.c
+++ b/ast.c
@@ -48,6 +48,36 @@ ast_statement_new_while (ast_expression_t *condition,
     return statement;
 }
 
+gboolean
+ast_is (ast_t           *ast,
+	ast_type_t       type,
+	int              subtype)
+{
+    if (ast->common.type != type)
+	return FALSE;
+    
+    switch (type)
+    {
+    case AST_DEFINITION:
+	return subtype == ast->definition.common.type;
+
+    case AST_STATEMENT:
+	return subtype == ast->statement.common.type;
+
+    case AST_EXPRESSION:
+	return subtype == ast->expression.common.type;
+
+    case AST_TYPE_SPEC:
+	return subtype == ast->type_spec.common.type;
+
+    case AST_PROGRAM:
+	return TRUE;
+    }
+
+    g_assert_not_reached();
+    return FALSE;
+}
+
 ast_statement_t *
 ast_statement_new_for (ast_expression_t *first,
 		       ast_expression_t *second,