Re: [Haskell-cafe] name lists

* Ben Gamari [2013-09-17 12:41:05-0400]

Roman Cheplyaka writes:

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* Ben Gamari [2013-09-17 10:03:41-0400]

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Another approach might be to introduce some notion of a name list which can appear in the export list. These lists could be built up by either user declarations in the source module or in Template Haskell splices and would serve as a way to group logically related exports. This would allow uses such as (excuse the terrible syntax),

Hi Ben,

Isn't this subsumed by ordinary Haskell modules, barring the current compilers' limitation that modules are in 1-to-1 correspondence with files (and thus are somewhat heavy-weight)?

E.g. the above could be structured as

module MyDataLenses where data MyData = MyData { ... } makeLenses ''MyData

module HelloWorld (module MyDataLenses, ...) where ...

True. Unfortunately I've not seen much motion towards relaxing this limitation[1].

Cheers,

- Ben

[1] http://ghc.haskell.org/trac/ghc/ticket/2551

I guess there simply were not many use cases for that. This may be one. At least if we are talking about changing the compiler anyway, it's better to stick with a well-understood and standardized mechanism. Roman