I made a quick script that checks for duplicated raws, and reports on them. It also counts the instances of each object type (CREATURE, ENTITY, etc. etc.). It should have some use when merging mods, or visualizing the size of your mods compared to vanilla (and other mods).

This is the binary/.exe version. It shouldn't have any dependencies, and should(I haven't tested it) work on any modern Windows OS. Put all the contents of the zip in the same folder somewhere.

=Settings (in df_duplisearch_settings.txt):=
"Raw folder path:"
Where your raws are located. "[HERE]" can be used as a short for the folder the .exe is placed in. Remember to place a "\" or "/" at the end of the path.
The path comes pre-set to "[HERE]/raw/objects/" so you can run it from your main DF folder without changing anything.

"Show duplicated names:"
Can be toggled on/off depending if you want to show "duplicated names". These are the in-game names (e.g "tiger:tigers:tiger" from "CREATURE:TIGER"), and so they don't cause duplication errors, but can still be confusing to the player. Note that some vanilla objects are recognized as "duplicated", i.e. skirt, short skirt, long skirt.

works for 0.44 and 0.47, and likely most earlier versions as well