[Haskell-cafe] GHCI Feature Request: Last Successful Compilation State Saved

[Daniel Patterson]

Chris, this is amazing! One question - do you have support for tramping in and running ghci remotely (or would that be easy to add)? I primarily develop inside virtual-machines, so while the source code lives where emacs lives, all the libraries are installed inside the virtual-machine (and the source also lives there, of course). 

On Aug 30, 2011, at 4:46 AM, Christopher Done wrote:

> Oh, I didn't reply all. Whoops.
> 
> On 28 August 2011 13:40, Christopher Done <chrisdone at googlemail.com> wrote:
>> On 27 August 2011 22:59, aditya siram <aditya.siram at gmail.com> wrote:
>>> I would like for the GHCI interpreter to save its environment before
>>> reloading a file and allowed the user to revert back to that state if the
>>> compilation was unsuccessful.
>>> 
>>> Many times I've changed files, loaded them, hit a compilation error and
>>> needed, for example, the inferred type signature of some function. Even
>>> though that function hasn't been changed I have to either fix my code, undo
>>> a bunch of changes or comment out the last change I made and reload in order
>>> to do a ":type" on the function. This really breaks the flow of development.
>> 
>> This has been bugging me for a long time and it's been on my TODO list
>> for haskell-emacs: https://github.com/chrisdone/haskell-emacs
>> 
>> I just implemented it. http://i.imgur.com/A71T5.png
>> 
>> I just run two ghci processes, one for compiling, one for merely
>> loading the code in when the former succeeds.
>> 
>> It's not a very pleasant hack but in conjunction with :set
>> -fobject-code it is fast and does not consume that much more memory.
>> Considering tibbe's report is 4 years old, I think this solution is
>> better than nothing.
>> 
>> Set hs-config-preliminary-load-file to t in hs-config.el and it will
>> do a preliminary load in a separate GHCi process.