Is this possible in PHP?

Question

Consider the following PHP snippet:

<?php

class Is
{
    function __get($key)
    {
        $class = __CLASS__ . '_' . $key;

        if (class_exists($class) === true)
        {
            return $this->$key = new $class();
        }

        return false;
    }

    function Domain($string)
    {
        if (preg_match('~^[0-9a-z\-]{1,63}\.[a-z]{2,6}$~i', $string) > 0)
        {
            return true;
        }

        return false;
    }
}

class Is_Domain
{
    function Available($domain)
    {
        if (gethostbynamel($domain) !== false)
        {
            return true;
        }

        return false;
    }
}

$Is = new Is();

var_dump($Is->Domain('google.com')); // true
var_dump($Is->Domain->Available('google.com')); // false

?>

Is it possible to call the Available() method like this (and still return solely true or false if the Available method is not called)?

var_dump($Is->Domain('google.com')->Available()); // false

If yes, how?

EDIT: Would this do the trick?

class Is
{
    function __get($key)
    {
        // same as before
    }

    function Domain($string)
    {
        if (preg_match('~^[0-9a-z\-]{1,63}\.[a-z]{2,6}$~i', $string) > 0)
        {
            return (bool) $this->Domain;
        }

        return false;
    }
}

class Is_Domain
{
    function __toString()
    {
        return true;
    }

    function Available($domain)
    {
        if (gethostbynamel($domain) !== false)
        {
            return true;
        }

        return false;
    }
}

Thanks in Advance!

PS: This snippet is truncated, so don't expect it to make it a lot of sense just by its own.

Answer 1

Essentially you want a method to return either a bool or an object based on whether a subsequent method call to the result is going to occur. I don't think this will be possible without some massive hack (e.g. reading the PHP file in yourself and looking ahead), and it shouldn't be because your objects shouldn't be worrying about the context in which they are used.

Instead you could get the first call to return an object which is relevant in both cases, e.g. DomainLookupResult, which has two methods e.g. Exists() and IsAvailable(). You could then do:

$result = $Is->Domain('google.com');
$isValid = $result->Exists();
$isAvaliable = $result->IsAvailable();

//or chaining:

$isValid = $Is->Domain('google.com')->Exists();
$isAvailable = $Is->Domain('google.com')->IsAvailable();