Fast byte replacement on string

[Andrew Barringer]

I'm implementing a requirement for a Google service that reads in part

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With urls..

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"To start, repeatedly URL-unescape the URL until it has no more
hex-encodings."

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Do lots of stuff here with url.

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Finally "After performing these steps, percent-escape all characters in
the URL which are <=3D ASCII 32, >=3D 127, or "%". The escapes should =
use
uppercase hex characters."

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Do any of you have a very fast way to do this?

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The implementation I have now is dreadfully slow, I'll spare you my
solution. J =20

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I need a solution that will work with Ruby 1.8.6 & 1.9.1

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Andy

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