And to make it more like the original code that classified lines
separately from checking and transforming them.

unlit preserves comments for Haddock's benefit. More complex algorithm to handle cases where we want blank lines (containing whitespace) to become comment lines in the output.

and a couple other trivial tidyups

I doubt it works or that anyone uses it.
If anyone genuinely does use it we can add it back in cabal-install.

It used to look for and warn about Setup.description files.
That's from a very very old transition which is now complete.
We can just ignore any files like that now.

Should allow satisfying deps from the given package db and should register
into that db. It is not thoroughly tested however.

Added a check for the existence of the license file (if one is
specified in a license-file: field) during description file
sanity checking.  If a license is specified but does not exist,
a warning is generated.  This patch resolves issue #180.

Though of course we cannot yet change the UserHooks interface so that it is
never given the LocalBuildInfo.

There was only one use and no point since rawSystem uses the path anyway.

so they are almost certainly useless to the debian folks anyway.

make it a .hs like everyone else uses

and jhc should just be putting its generated files under dist/ anyway.
The latter issue is filed as bug #219.

Saves printing an error message when it fails.

So it doesn't use a temp file to capture the output.
Since runInteractiveProcess is only available on ghc we
use the temp file method for other implementations.

Many Setup.hs files import Distribution.Setup so this unbreaks them.
It's marked DEPRECATED so will generate a warning for scripts that use it.
This patch is only going to the cabal-1.2 branch, not HEAD.

to $HOME/.cabal on unix and on WinXP: (not sure about vista)
C:\Documents And Settings\user\Application Data\cabal

This is needed to separate Cabal and subprogram output if stdout is
buffered (e.g. a file), especially if stdout and stderr are the same.

Fixes ticket #11. Though the section could do with a bit more detail.
It corresponds to what's on the wiki:
http://hackage.haskell.org/trac/hackage/wiki/StableInterfaces

The System.IO.openTempFile is much better because it opens the temp files
securely. Howver it is only available in base-2 and only of GHC. In base-3
it is available for all implementations. So in practice that means it's only
for GHC and we have to use our compatability implementation for hugs and
nhc98. Not sure of the status for jhc.

ghc-6.4 and above recognise the OPTIONS_GHC pragma.
ghc-6.6 and above recognise the LANGUAGE pragma.
Added OPTIONS_JHC and OPTIONS_NHC pragmas with equivalant flags.

Dissalows version strings like "1.05". It'd have to be "1.5" or "1.0.5".
That is, leading '0's in version components are no longer allowed.
The Version parser & pretty printer should now be exactly 1-1 and invertable.

Previusly everyone got the compat version, except for ghc and hugs which
opted out. Now just nhc98 opts in.

No longer inlcude compatability hacks and remove code that handles
the old style of ghc-pkg package registration files.