how can I diff two sections of the same file?

Question

I have a source file with two similar yet subtly different sections. I\'d like to merge the two sections into one subroutine with a parameter that handles the subtle difference

Answer 1

KDiff3 is open source and available on several platforms including Win32 and Linux.

It has the "manual alignment" feature discussed by Gishu about Beyond Compare (which by the way I haven't been using personally but is considered a great tool by many people I know).

See this answer for more examples.