Libraries and tools/Time library

Now in the base libraries, due to be released with GHC 6.6. Data.Time

The API is well designed, but not particularly obvious for simple use cases. Hopefully we can collect a number of common examples here.

If you want to use Data.Time with GHC 6.4, you will need to install a number of libraries it depends on first. The process is:

 darcs get --partial http://www.cse.unsw.edu.au/~dons/code/fps
 normal cabal configure, build, install

 darcs get http://darcs.haskell.org/packages/Win32
 Edit Win32.cabal, add fps to build-depends.
 normal cabal configure, build, install

 darcs get http://semantic.org/TimeLib/TimeLib
 There are two packages here: time and fixed. Ignore time.
 Go into fixed and do cabal configure, build, install

 darcs get http://darcs.haskell.org/packages/time
 Edit time.cabal, add fixed and Win32 to build-depends.
 create Setup.hs:
   import Distribution.Simple
   main = defaultMainWithHooks defaultUserHooks
 From MSYS shell, not Windows cmd.exe:
   autoreconf
   runhaskell Setup.hs configure
   runhaskell Setup.hs build
   runhaskell Setup.hs install