File compare/merge

[Vladimir Panteleev]

On Tuesday, 2 April 2013 at 10:44:05 UTC, Stewart Gordon wrote:
> Nowadays, CSDiff, the compare feature in Notepad++, or good old 
> fc, depending on what is best for the circumstances.  At least 
> to compare - merging isn't something I've had to do much in my 
> time.
>
> Is anybody here writing a file-compare tool in D?  It would be 
> interesting to see how good a diffing algorithm we can come up 
> with. Maybe making use of levenshteinDistanceAndPath.

I once had to compare two very large (GBs in size) files 
(filesystem listings). Every diff program I tried crashed 
miserably. I wrote my own:
http://dump.thecybershadow.net/7558f727792723efdb159197e50d125f/uniqdiff.d

It's nothing fancy (no std.algorithm), and is greedy (it works on 
the assumption that once it finds one line that matches on both 
sides, then the diff chunk is over).