php version_compare（）在localhost上失败，在服务器上运行

Question

This conditional code execution if statement is right out of the php manual:

// version_compare ( string $version1 , string $version2 [, string $operator ] )
// http://php.net/manual/en/function.version-compare.php
if (version_compare(PHP_VERSION, '5.3.0') >= 0)
{
    //echo 'I am at least PHP version 5.3.0, my version: ' . PHP_VERSION . "
";
    include_once( DOMAIN_PATH . "sitewide/functions/make_comparer.php" );
    usort($market_and_volume, make_comparer(['exchange_volume', SORT_DESC], ['exchange', SORT_DESC]));   
}

The above code runs free of error on the production server. On localhost php version 5.2.9-2 which theoretically fails the version_compare() function it throws an error:

Parse error: parse error, expecting `')'' in test.php on line 61

Normally i might not care since its running on the 5.4.39 production server, however I plan to use this snippet on almost every localhost page which as it stands would impede future development.

Any ideas?

Answer 1

The problem is you are using the shorthand array notation. [...]. Unfortuantely this is only supported from PHP 5.4.0 and up. Even though the "bad" code is never run it fails to compile so throws an error.

This can be fixed by using the array(...) notation like so.

// version_compare ( string $version1 , string $version2 [, string $operator ] )
// http://php.net/manual/en/function.version-compare.php
if (version_compare(PHP_VERSION, '5.3.0') >= 0)
{
    //echo 'I am at least PHP version 5.3.0, my version: ' . PHP_VERSION . "
";
    include_once( DOMAIN_PATH . "sitewide/functions/make_comparer.php" );
    usort($market_and_volume, make_comparer(array('exchange_volume', SORT_DESC), array('exchange', SORT_DESC)));   
}

REFERENCE: http://php.net/manual/en/language.types.array.php