Support for additional .ghci files in GHCi.

[SamAnklesaria]

Currently, GHCi only loads a single .ghci file. As a result, all user customizations and macros must be centralized to one location. Additionally, this leaves limited potential for tools using GHCi (cabal-install, for example) to customize the interpretation environment. I propose adding a -ghci-script flag for each additional .ghci file to be loaded in the order specified on the command line after the usual .ghci file in the current or user directory.

[duncan]

Note that we think we need this for the cabal repl feature that Sam is implementing for his GSoC project.  http://lambdasandwich.blogspot.com/2011/06/reloading-ghci.html

Our plan is for cabal to generate a ghci script that rebinds the :reload command so that it calls back out to cabal to re-run pre-processors (hsc2hs etc). Then cabal repl will invoke ghci -ghci-script dist/ghci or something like that.

Sam will be preparing a patch. I'll do the first review. If possible we're aiming for inclusion in the 7.2 release.

[duncan]

Code looks good to me.

[igloo]

Applied, thanks

[SamAnklesaria]

fixed mistake in previous patch

[SamAnklesaria]

uses dynamic flags instead. requires old patch to be reverted.

[SamAnklesaria]

I did not intend to attach 5265-fix.2.patch. Ignore it please. dyn5265.patch is the real dynamic version.

[SamAnklesaria]

uses dynamic flags. requires old patch to be reverted

[duncan]

Hmm, seems to be confusion about this. The current user guide claims (here and here) that the -ghci-script flag is supported, however my ghci-7.4.1 says it knows nothing about it.

Those two changes to the user guide are included in Sam's patch, but the rest of that patch doesn't seem to be there.

As far as I can see, the attached dyn5265.patch is good, so I'm changing this ticket status to 'patch'.

[simonmar]

Paulo, could you validate and push please?

[p.capriotti@…]

commit 76bde331226e933b65b6433e983c50da1ce3b532

Author: Paolo Capriotti <p.capriotti@gmail.com>
Date:   Wed Apr 11 14:34:25 2012 +0100

    Add support for additional .ghci files in GHCi (#5265)
    
    Patch by Sam Anklesaria <amsay@amsay.net>

 compiler/main/DynFlags.hs  |    7 ++++++-
 docs/users_guide/flags.xml |    6 ++++++
 docs/users_guide/ghci.xml  |   12 ++++++++++++
 ghc/InteractiveUI.hs       |    4 ++--
 4 files changed, 26 insertions(+), 3 deletions(-)

[p.capriotti@…]

commit ab52df86f5f76da6e19ee6562792ea43972a6f24

Author: Paolo Capriotti <p.capriotti@gmail.com>
Date:   Wed Apr 11 14:19:25 2012 +0100

    Revert "trac #5265 (support for additional .ghci files)"
    
    This reverts commit 991f141989940c897cb2fc3dba7b5b49342d402a.

 compiler/main/StaticFlags.hs |   11 +----------
 docs/users_guide/flags.xml   |    6 ------
 docs/users_guide/ghci.xml    |    4 ----
 ghc/InteractiveUI.hs         |    3 +--
 4 files changed, 2 insertions(+), 22 deletions(-)