重命名内置的PHP函数，而不使用PECL扩展

I want to replace 'date' function with another function. Using 'rename_function' and 'override_function' are a solution for me, but is there any other way to solve the problem without using PECL extension?

This isn't a perfect solution because you must add use function in your php files. (use function works on php 5.6.0 or above):

namespace OverriddenFunctions {
    function target($arg1) {
        return "Overridden result!"
    }
}

namespace {
    use function OverriddenFunctions\target;
    echo target('arg1');
}

Thanks to Mark Baker.