PHP Shorthand ternary operator “?:” Parse error un

2019-01-23 11:35发布

I've just uploaded some old PHP files to a new server and am getting parse errors (Unexpected ':') on shorthand ternary ops. eg:

$y = $x ?: "Some default";

php version is 5.2.16 The code is littered with these shorthand ?:, so before changing them all I thought I'd see if anyone knows anything about this as I've not used PHP for a while now.

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Juvenile、少年°
2楼-- · 2019-01-23 11:59

Since you are using php 5.2.16, your ternary requires 2 options e.g

$y = $x? "???" : "Some default";

Variable = condition ? true value : false value ;

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Viruses.
3楼-- · 2019-01-23 12:17

This is only available since PHP 5.3

The expression (expr1) ? (expr2) : (expr3) evaluates to expr2 if expr1 evaluates to TRUE, and expr3 if expr1 evaluates to FALSE.

Since PHP 5.3, it is possible to leave out the middle part of the ternary operator. Expression expr1 ?: expr3 returns expr1 if expr1 evaluates to TRUE, and expr3 otherwise.1

See this example for more context.

or a more useful but note in the comments: http://www.php.net/manual/en/control-structures.if.php#102060


1http://php.net/manual/en/language.operators.comparison.php

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