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Date: Wed, 17 Jan 2018 18:47:49 +0100
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Subject: [RFC] [DISCUSSION] Improve null-coalescing operator (??) adding empty
 check (??:)
From: info@eordes.com (Lito)

Related with Request #75833 https://bugs.php.net/bug.php?id=75833

 From PHP 7 null-coalescing operator is a great option to avoid a 
previous exists check with isset.

But I think that this comaparison can be improved adding a ternary 
operator like ??: and check also empty values.

Example:

--------------------------------------

<?php

$foo = '';

// Current response with ternary operator

echo $foo ?: 'default'; // 'defaut'

// Current response with null-coalescing operator

echo $foo ?? 'default'; // ''

// Possible response with ternary null-coalescing operator

echo $foo ??: 'default'; // 'defaut'

// Same response with current PHP available code

echo (isset($foo) && $foo) ? $foo : 'default'; // 'default'

/** ------------------------------- **/

$foo = false;

// Current response with ternary operator

echo $foo ?: 'default'; // 'defaut'

// Current response with null-coalescing operator

echo $foo ?? 'default'; // false

// Possible response with ternary null-coalescing operator

echo $foo ??: 'default'; // 'defaut'

// Same response with current PHP available code

echo (isset($foo) && $foo) ? $foo : 'default'; // 'default'

/** ------------------------------- **/

$foo = null;

// Current response with ternary operator

echo $foo ?: 'default'; // 'defaut'

// Current response with null-coalescing operator

echo $foo ?? 'default'; // 'defaut'

// Possible response with ternary null-coalescing operator

echo $foo ??: 'default'; // 'defaut'

// Same response with current PHP available code

echo (isset($foo) && $foo) ? $foo : 'default'; // 'default'

/** ------------------------------- **/

unset($foo);

// Current response with ternary operator

echo $foo ?: 'default'; // PHP Notice:  Undefined variable: foo

// Current response with null-coalescing operator

echo $foo ?? 'default'; // 'defaut'

// Possible response with ternary null-coalescing operator

echo $foo ??: 'default'; // 'defaut'

// Same response with current PHP available code

echo (isset($foo) && $foo) ? $foo : 'default'; // 'default'

--------------------------------------

What about?

Thanks!
Lito.