Stack Overflow Q12435954

http://stackoverflow.com/questions/12435954/difference-in-laziness-of-lookahead-assertions-between-javascript-and-php

by acheong87 November 02, 2012

HTML

<pre id="output"></pre>

JavaScript

$('#output').append('foobar'.replace(/(?=(bar))/, '$1') + "\n");
$('#output').append('foobar'.replace(/(?=(bar))?/, '$1') + "\n");
$('#output').append('foobar'.replace(/(?:(?=(bar)))?/, '$1') + "\n");

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Stack Overflow Q12435954

http://stackoverflow.com/questions/12435954/difference-in-laziness-of-lookahead-assertions-between-javascript-and-php

HTML

JavaScript

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