Library proposal: Add System.Info.isWindows

[Neil Mitchell]

Hi

See bug: http://hackage.haskell.org/trac/ghc/ticket/1590

Currently the recognised way to test if your application is being run
on Windows is:

import System.Info

.... = os == "mingw"

This is wrong on so many levels!

# The return result of os is NOT an operating system

# The result mingw does not imply that mingw is installed

# String comparisons are not very safe, a typo stops this working

# In GHC this comparison will take place at runtime, even though its a constant

Since nearly all uses of System.Info.os are to check if the operating
system is Windows, adding an explicit isWindows function would
simplify things.

Proposal:

Add System.Info.isWindows :: Bool

This value should return True on all Windows systems (Win 1.0 ...
Vista), and False on all other systems.

Thanks

Neil