PHP associative array parse error that only affects some machines
<p>This code fails on some machines:</p>

<pre><code>// Parse error: syntax error, unexpected '[' ...
return json_encode(self::GenerateSomeAssociativeArray($meta_file)["list"]);
</code></pre>

<p>but this effectively identical version works on all machines:</p>

<pre><code>$foo = self::GenerateSomeAssociativeArray($meta_file);
return json_encode($foo['list']);
</code></pre>

<p>I assume it's a versioning issue, but I'm unable to find information on the difference, probably because I'm unfamiliar with the terminology to search.</p>
