Merge spawn' into spawn

[Gabriella439]

spawn' is more general than spawn, but only exists as a separate function because spawn came first and I didn't want to break backwards compatibility.

Since I plan on implementing issue #14 which will be a (slightly) backwards incompatible change, I've been considering taking advantage of this version bump to also fully replace spawn with the more general spawn' function.

I'm opening this issue to solicit opinions for or against this change.

[quchen]

I don't see why not. The change will create static errors, and the fix is trivial.

[PierreR]

While working on spawn I would suggest to transpose (read, write) <- case buffer of into (write, read) to mimic the return value (output, input). This would increase the code readability because output is writing into the queue while input is reading from it.

https://github.com/Gabriel439/Haskell-Pipes-Concurrency-Library/blob/master/src/Pipes/Concurrent.hs#L174

PS: if it is OK and easier for you I can issue a pull request.

[Gabriella439]

Yeah, I agree that switching their order in the code makes more sense. If you write up a pull request then I will merge it.

[Gabriella439]

I will delay merging these for at least one release. There are lots of non-breaking changes that I can make and I would like people to preview those changes first before beginning to make breaking changes.