PHP: Wiki style before/after edit comparisons of text

Question

Say I had 2 paragraphs of text to compare..

1) "Text text text text text
text text text text text
text text text text text"

2) "Text text text text text
text text text NEW TEXT text text
text text text text text"

How would I go about finding out what the different parts are from the first paragraph to the next (like what you see in wiki edits)? My only guess would be to explode() each paragraph by "\n" and do a line by line comparison, but I'm sure there is much more to it

Answer 1

You can use a tool such as diff

Answer 2

There's a PEAR library for doing textual diffs that should help instead of reinventing the wheel:

http://euk1.php.net/package/Text_Diff

Answer 3

Er, I should've done this sooner, but apparently pastebin.com is open source and on their site is their code is hosted. I peered into it and saw that they were using this: http://www.holomind.de/phpnet/diff2.src.php