gistfile1.php

<?php
namespace MSS\Utility;

function _wantScalarType($function, $values) {
    foreach ($values as $value)
        if (!$function($value))
            throw new \InvalidArgumentException();
}

function wantBool() {
    _wantScalarType('is_bool', func_get_args());
}

function wantInt() {
    _wantScalarType('is_int', func_get_args());
}

function wantFloat() {
    _wantScalarType('is_float', func_get_args());
}

function wantString() {
    _wantScalarType('is_string', func_get_args());
}

function wantArrayOf($type) {
    $arrays = array_slice(func_get_args(), 1);
    foreach ($arrays as $values) {
        switch ($type) {
            case 'bool':
                call_user_func_array('MSS\Utility\wantBool', $values);
                break;

            case 'int':
                call_user_func_array('MSS\Utility\wantInt', $values);
                break;

            case 'float':
                call_user_func_array('MSS\Utility\wantFloat', $values);
                break;

            case 'string':
                call_user_func_array('MSS\Utility\wantString', $values);
                break;

            default:
                foreach ($values as $value)
                    if (!($value instanceof $type))
                        throw new \InvalidArgumentException();
        }
    }
}