Export lists in modules

John Meacham john at repetae.net
Wed Feb 22 07:35:35 EST 2006

On Wed, Feb 22, 2006 at 12:07:44PM +0000, Malcolm Wallace wrote:
> At the moment, only one type signature is permitted per entity (except
> for FFI foreign exports, where the exported signature may be more
> specific than the definitional signature).  My proposal is that the
> normal export list can have signatures /in addition to/ the definitional
> signature, but that if there are thus two signatures for an entity, they
> must be identical.  This is to prevent the case where one modifies the
> definition of the function, making it more general, but forgets to
> modify the corresponding export.

Another reason we might want to allow both is for scoped type variables.
We should probably only allow type variables in the definitional
signature to scope over the body of the function since it just doesn't
feel right for something in the export list to scope over the body of a
function in the module.


John Meacham - ⑆repetae.net⑆john⑈

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