JavaScript: using constructor without operator 'new'

Posted by GetFree on Stack Overflow See other posts from Stack Overflow or by GetFree
Published on 2009-12-18T13:56:54Z Indexed on 2010/03/23 19:33 UTC
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JavaScript

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contructor

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object-construction

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new-operator

Please help me to understand why the following code works:

<script>
    var re = RegExp('\\ba\\b') ;
    alert(re.test('a')) ;
    alert(re.test('ab')) ;
</script>

In the first line there is no new operator.

As far as I know, a contructor in JavaScript is a function that initialize objects created by the operator new and they are not meant to return anything.

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