diff --git a/Makefile b/Makefile
index 242e578..537fec1 100644
--- a/Makefile
+++ b/Makefile
@@ -50,6 +50,9 @@ clean:
 lua:
 	@cd Lua && make
 
+luatest:
+	@cd Lua && make test
+
 test: $(NAME)
 	./$(NAME) Comment -r '[@0]' >/dev/null
 	./$(NAME) -g ./grammars/bp.bp '{Grammar}' ./grammars/bp.bp >/dev/null
@@ -100,4 +103,4 @@ profile_grammar: bp
 profile_pattern: bp
 	perf stat -r 1 -e L1-dcache-loads,L1-dcache-load-misses,L1-dcache-stores -e cycles ./bp -f plain -p 'id parens' /usr/include/*.h >/dev/null
 
-.PHONY: all clean install install-lib uninstall leaktest splint test tutorial lua profile
+.PHONY: all clean install install-lib uninstall leaktest splint test tutorial lua profile luatest
diff --git a/utils.h b/utils.h
index 0973926..1819c75 100644
--- a/utils.h
+++ b/utils.h
@@ -13,34 +13,16 @@
 
 #define S1(x) #x
 #define S2(x) S1(x)
-#define __LOCATION__ __FILE__ ":" S2(__LINE__)
 
-#define DEFINE_CHECK_TYPE(t, name, var, expr) \
-static inline t _check_##name(t var, const char *fmt, ...) { \
-    if (!(expr)) {\
-        va_list args;\
-        va_start(args, fmt);\
-        verrx(1, fmt, args);\
-        va_end(args);\
-    }\
-    return var;\
-}
-DEFINE_CHECK_TYPE(void*, ptr, p, p);
-DEFINE_CHECK_TYPE(int, int, i, i >= 0);
-DEFINE_CHECK_TYPE(ssize_t, ssize_t, i, i >= 0);
-DEFINE_CHECK_TYPE(char, char, c, c);
-DEFINE_CHECK_TYPE(_Bool, bool, b, b);
+#define require(e, msg) ({\
+    __typeof__(e) __expr = e; \
+    if (_Generic(__expr, int: (ssize_t)__expr < 0, ssize_t: (ssize_t)__expr < 0, default: !__expr)) errx(1, __FILE__":"S2(__LINE__)": " msg); \
+    __expr; \
+})
 
-#define PP_ARG_N(_1,_2,_3,_4,_5,_6,_7,_8,_9,_10,_11,_12,_13,_14,_15,_16,_17,_18,_19,_20,_21,_22,_23,_24,_25,_26,_27,_28,_29,_30,_31,N,...) N
-#define PP_NARG(...) PP_ARG_N(__VA_ARGS__,31,30,29,28,27,26,25,24,23,22,21,20,19,18,17,16,15,14,13,12,11,10,9,8,7,6,5,4,3,2,1,0)
-
-#define _require_fmt(e, ...) _Generic((e), _Bool: _check_bool, int: _check_int, ssize_t: _check_ssize_t, char: _check_char, void*: _check_ptr, default: _check_ptr)((e), ""__VA_ARGS__)
-#define require(e, ...) (PP_NARG(e,##__VA_ARGS__) > 1 ? _require_fmt((e), __LOCATION__": "__VA_ARGS__) : _require_fmt((e), __LOCATION__": `%s` failed", #e))
-#define require_true(e, ...) (PP_NARG(e,##__VA_ARGS__) > 1 ? _require_fmt((_Bool)(e), __LOCATION__": "__VA_ARGS__) : _require_fmt((_Bool)(e), __LOCATION__": `%s` is not true", #e))
-
-#define new(t) _check_ptr(calloc(1, sizeof(t)), "`new(" #t ")` allocation failure")
-#define checked_strdup(s) _check_ptr(strdup(s), "`checked_strdup(" #s ")` allocation failure")
-#define grow(arr,n) _check_ptr(realloc(arr,sizeof(arr[0])*(n)), "`grow(" #arr ", " #n ")` allocation failure")
+#define new(t) require(calloc(1, sizeof(t)), "`new(" #t ")` allocation failure")
+#define checked_strdup(s) require(strdup(s), "`checked_strdup(" #s ")` allocation failure")
+#define grow(arr,n) require(realloc(arr,sizeof(arr[0])*(n)), "`grow(" #arr ", " #n ")` allocation failure")
 
 #define streq(a, b) (strcmp(a, b) == 0)