Replacing multiple patterns in a block of data

Posted by VikrantY on Stack Overflow See other posts from Stack Overflow or by VikrantY
Published on 2010-03-23T15:56:34Z Indexed on 2010/03/23 23:43 UTC
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regex

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JavaScript

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algorithms

Hi All,

I need to find the most efficient way of matching multiple regular expressions on a single block of text. To give an example of what I need, consider a block of text:

"Hello World what a beautiful day"

I want to replace Hello with "Bye" and "World" with Universe. I can always do this in a loop ofcourse, using something like String.replace functions availiable in various languages.

However, I could have a huge block of text with multiple string patterns, that I need to match and replace.

I was wondering if I can use Regular Expressions to do this efficiently or do I have to use a Parser like LALR.

I need to do this in JavaScript, so if anyone knows tools that can get it done, it would be appreciated.

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