Javascript String.replace() ,ambiguous results

Question

See my code

<html>
<body>

<script type="text/javascript">

var str="Visit Microsoft!";

document.write( str = str.replace("",'ss'));

</script>
</body>
</html>

The output is

 ssVisit Microsoft!

Why is it happening.?

replace with a string will only replace the first occurrence of that string. You pass an empty string, which is found at the beginning of the string ("something".indexOf("") returns 0). — Felix Kling
– Felix Kling, Commented Feb 23, 2012 at 19:23
Between the beginning of the string and the first character, there is nothing. Same goes for anything between characters. The empty string can be found between any characters (you can do the same what Alex did, e.g. "foo" + "" + "bar" === "foobar"). — Felix Kling
– Felix Kling, Commented Feb 23, 2012 at 19:26
To further illustrate, here's what happens, if you replace all empty/zero-length strings in str: str.replace(new RegExp("", "g"), "-") → "-V-i-s-i-t- -M-i-c-r-o-s-o-f-t-!-" — Flambino
– Flambino, Commented Feb 23, 2012 at 19:29

Community · Accepted Answer · 2017-05-23 09:59:28Z

2

This is correct because every string begins with an empty string. See below post for more info:

CommunityBot

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answered Feb 23, 2012 at 19:27

Pramod

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