bool GMQCC_WARN ast_value_params_add(ast_value*, ast_value*);
bool ast_compare_type(ast_expression *a, ast_expression *b);
+ast_expression* ast_type_copy(lex_ctx ctx, const ast_expression *ex);
+#define ast_type_adopt(a, b) ast_type_adopt_impl((ast_expression*)(a), (ast_expression*)(b))
+bool ast_type_adopt_impl(ast_expression *self, const ast_expression *other);
/* Binary
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