Diff tool that can compare sub-sections of files

Question

I'm looking for a diff tool that will allow me to compare just a sub-section of a file with a section of another file, or even of itself. Preferably eclipse based but will take all suggestions.

Yes I know I can copy out the two sections into different files and compare those, but that is very tedious when you are trying to do a large amount of refactoring.

Basically I'm trying to remove as much duplicated code as possible from a code base that is suffering from a great deal of ctrl-V 'inheritance' ;-) However the pasted parts have evolved apart a little over time.

Answer 1

I've been playing with Atomiq, which finds duplicates within a single file. So far it looks to be a decent tool.