cabal design
Simon Peyton-Jones
simonpj at microsoft.com
Wed Aug 17 04:17:40 EDT 2005
| > Some kind of 'grafting' or 'mounting' scheme would be needed to
bring a
| > package into the package namespace.
|
| I disagree that this necessarily mandates a grafting or mounting
| scheme. Whilst it might be useful, even desirable, it is a separate
| question.
I agree that it's a separate question. Hence (b) of my message. If you
want to
import module A from package P and
import module A from package Q
into a single module M of a program,
you can always do this:
make a new module AP, that imports A and re-exports it all;
compile AP with package P visible and Q hidden
ditto for AQ
make M say "import AP; import AQ"
That's essentially what you suggested. Of course it means that any
"import A.B.C" has to be understood wrt a namespace that may change from
module to module. I guess that one merit of the grafting scheme is that
you could make a single package-grafting configuration that would apply
to the whole of a program, so that within that program modules were
consistently and uniquely named.
But yes it's a separate question.
Simon
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