What does "?:" mean in PHP? [duplicate]

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Reference Guide: What does this symbol mean in PHP? (PHP Syntax) (25 answers)

What is ?: in PHP 5.3? [duplicate] (3 answers)

Closed 9 years ago.

While browsing the code of an open source PHP library I spotted this line:

$path = $path ?: $this->guessPackagePath();

This is not the ternary operator like it usually apprears. Would anyone explain what is going on in it?

Answer 1

It's a shortcut for

$path = $path ? $path : $this->guessPackagePath();

which comes from PHP 5.3