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I'm trying to use String.sub! in ruby and it substitutes way too much.

The regex i'm using. You can see it's matching too much: http://rubular.com/r/IUav4KEFWH

<rb>.+<\/rb>

it selects from the first to the last and I want it just to select the first pair. is there another version of sub I'm not aware of, or a better way to sub

it would be easy to turn of multi-line and put them on separate lines but I don't want to sacrifice multi-lining

hwnd
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maek
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    Please put your code in your question. It's OK to have the link as well, but questions should be able to survive broken links. – Cary Swoveland Sep 14 '14 at 08:08

3 Answers3

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Your regex is too greedy:

<rb>.+<\/rb>

Make it non-greedy using:

<rb>.+?<\/rb>

Rubular Demo

anubhava
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It matches from the first <rb> tag up until the very last </rb> tag because + is a greedy operator meaning it will match as much as it can and still allow the remainder of the regular expression to match.

You want to use +? for a non-greedy match meaning "one or more — preferably as few as possible". 

<rb>.+?</rb>

Note: A parser to extract from HTML is recommended rather than using regular expression.

hwnd
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You can try this variant:

<rb>(?>(?!<\/rb>).)*+<\/rb>

Demo

Or if you want:

<rb>[^<]+<\/rb>

Demo

See the difference between .*? And [^<]+ in this DEMO

walid toumi
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