Request: Open Module Resolution

[Simon Marlow]

On 05 May 2005 17:38, S. Alexander Jacobson wrote:

> On Wed, 4 May 2005, Simon Marlow wrote:
> 
>> Instead, let me point you at the place in GHC to insert your
>> resolver. In the module Finder, we have:
>> 
>> findModule :: HscEnv -> Module -> Bool -> IO FindResult
> 
> Oh, this is great!  Then let me be more precise in my request:
> 
> I am looking for a way for the user to provide a function to handle
> NotFound results.  I want the user to be able to supply a function
> that wraps findModule (with the exact same type signature).
>
>> You can almost replace findModule with your own resolver.  However,
>> the question is what do you do for modules like "Prelude": it sounds
>> like you'll need to have pre-compiled code for all the standard
>> libraries around (I assume you want to avoid using packages).
> 
> So the wrapper function can let the default findModule function
> operate and only handle the case where findModule returns NotFound.
> 
> The key point here is I'd like a way to do this that doesn't requiring
> recompiling GHC every time you change the wrapper function.
> 
> And I'd like the ability to reuse these user findModule functions
> with multiple Haskell compilers.
> 
> Is this possible?

Certainly.  But there's no easy way to say this:  I think you're going
to have to do it yourself (or find some kind soul to do it).  Of course
we'll incorporate the changes as long as they don't break anything else.

Cheers,
	Simon