Name = input("What is your name?","Creation",src) as null|text
for(var/mob/M in world)
if(Name == M.name)
alert("Somebody else has that name!","Error")
Create()
but as far as i can tell that only reads the current people in the world. i want it to check all the save files for the name. can that be done or would i have to make a different save file that would be made just to save the names of every mob made and then get it to read from that. but then that holds the problem of if that file is deleted people can create duplicate names :(.
I'd also recommend a 'delete savefile' verb that reads the savefile, removes the names and then deletes the .sav file.
It'll just require a little effort so that all character deletion/addition is handled properly.
From the sounds of it you know enough to make these sorts of systems without my help, but if you do get stuck somewhere just ask.