How to just show lines which are different?

[cwtuan]

I have two file which contains a thousand line but only few of lines are different.
Is it possible to show the lines which are different instead of the whole file?

[JackuB]

Could you elaborate on the use case? I'm thinking what's the scenario here and whether do you need to show them AND edit them? Or merge them?

Thinking that adding a plain code folding from Ace could do the trick.

[cwtuan]

If there is a large file which is changed in a few lines, showing the whole file may make the container very long.