> Why the duplication? I have not yet observed Metal using different programs for each.
I'm guessing whoever designed the system wasn't sure whether they would ever need to be different, and designed it so that they could be. It turned out that they didn't need to be, but it was either more work than it was worth to change it (considering that simply passing the same parameter twice is trivial), or they wanted to leave the flexibility in the system in case it's needed in future.
I've definitely had APIs like this in a few places in my code before.
I'm guessing whoever designed the system wasn't sure whether they would ever need to be different, and designed it so that they could be. It turned out that they didn't need to be, but it was either more work than it was worth to change it (considering that simply passing the same parameter twice is trivial), or they wanted to leave the flexibility in the system in case it's needed in future.
I've definitely had APIs like this in a few places in my code before.