first-class modules
Jon Fairbairn
Jon.Fairbairn@cl.cam.ac.uk
Tue, 26 Mar 2002 18:07:36 +0000
David Feuer wrote:
> A number of people have discussed the use of implicit parameters to
> mimic global variables in Haskell. I am wondering if any have done the=
> same for a first-class module system such as that proposed by Shields
> and Jones. It seems to make a tremendous amount of sense to do it that=
> way:
> =
> 1. semi-constant values: Things that are calculated
aren't a problem unless they depend on something that's
input at run-time.
> or input at the beginning of the program could be handled
> by Main.main, which would pass the results to the Second
> module, whose main function it could then call. This
> seems much more natural than the implicit parameter
> approach for this purpose.
This approach could also solve the "here document" question.
If we allow modules that define a value rather than names
and are in a range of different syntaxes, we can import the
value at the point of use. Having foreign values in files
would allow things such as the import of a font metric file
as a constant, which would be much nicer than reading it
from a file and having to pass it around.
J=F3n