Javascript undefined behavior with string.replace

Posted by epochwolf on Stack Overflow See other posts from Stack Overflow or by epochwolf
Published on 2010-04-25T02:52:36Z Indexed on 2010/04/25 3:03 UTC
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I've been messing around with string.replace and I noticed something very odd with Webkit and Firebug's javascript consoles.

I can repeat this behavior in a blank browser window. (Look at the first and last lines)

>>> "/literature?page=".replace(/page=/i, "page=2")
"/literature?page="

>>> "/literature?page=".replace("page=", "page=2")
"/literature?page=2"

>>> "/literature?page=".replace(/page=/, "page=2")
"/literature?page=2"

>>> "/literature?page=".replace(/page=/i, "page=2")
"/literature?page=2"

Just so nobody thinks I mistyped something, here are screenshots.

Firebug (3.0.14)

firefbug

Webkit (Latest nightly as of this post's creation.)

webkit

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