The is_null() is useless now, as it always returns FALSE.

engine/builtin.c

@@ -94,23 +94,6 @@ static int PH7_builtin_is_string(ph7_context *pCtx, int nArg, ph7_value **apArg)
 	ph7_result_bool(pCtx, res);
 	return PH7_OK;
 }
-/*
- * bool is_null($var)
- *  Finds out whether a variable is NULL.
- * Parameters
- *   $var: The variable being evaluated.
- * Return
- *  TRUE if var is NULL. False otherwise.
- */
-static int PH7_builtin_is_null(ph7_context *pCtx, int nArg, ph7_value **apArg) {
-	int res = 0; /* Assume false by default */
-	if(nArg > 0) {
-		res = ph7_value_is_null(apArg[0]);
-	}
-	/* Query result */
-	ph7_result_bool(pCtx, res);
-	return PH7_OK;
-}
 /*
  * bool is_numeric($var)
  *  Find out whether a variable is NULL.
@@ -7471,7 +7454,6 @@ static const ph7_builtin_func aBuiltInFunc[] = {
 	{ "is_float", PH7_builtin_is_float    },
 	{ "is_int", PH7_builtin_is_int      },
 	{ "is_string", PH7_builtin_is_string   },
-	{ "is_null", PH7_builtin_is_null     },
 	{ "is_numeric", PH7_builtin_is_numeric  },
 	{ "is_scalar", PH7_builtin_is_scalar   },
 	{ "is_array", PH7_builtin_is_array    },

engine/vm.c

@@ -1120,7 +1120,7 @@ PH7_PRIVATE sxi32 PH7_VmMakeReady(
 	}
 	/* Register built-in constants [i.e: PHP_EOL, PHP_OS...] */
 	PH7_RegisterBuiltInConstant(&(*pVm));
-	/* Register built-in functions [i.e: is_null(), array_diff(), strlen(), etc.] */
+	/* Register built-in functions [i.e: array_diff(), strlen(), etc.] */
 	PH7_RegisterBuiltInFunction(&(*pVm));
 	/* Initialize and install static and constants class attributes */
 	SyHashResetLoopCursor(&pVm->hClass);