[m-dev.] io streams

Peter Schachte schachte at cs.mu.OZ.AU
Thu Jan 6 10:24:24 AEDT 2000

On Wed, Jan 05, 2000 at 07:32:57PM +1100, Fergus Henderson wrote:
> On 05-Jan-2000, Peter Schachte <schachte at cs.mu.OZ.AU> wrote:
> > This is where default methods are important:  they allow you to add new
> > methods to type classes without forcing every instance declaration
> > (which may be in user code) to change, as long as the new methods have
> > defaults.  It may even be possible to change an existing ordinary
> > library predicate into a method without changing code that uses it,
> > provided the existing code doesn't explicitly module qualify calls to
> > it (would this be possible, DJ?).
> That would be possible.  It would be possible even if the calls
> where module qualified, so long as the type class and the
> library predicate are defined in the same module.

I thought *that* was not permitted, since that means there is more
than one "predicate" with the same arity and argument types in the
same module?  If that is allowed, I'm glad to hear it.

Peter Schachte                     We must not think that computation
mailto:schachte at cs.mu.OZ.AU        ... has place only in numbers.
http://www.cs.mu.oz.au/~schachte/      -- Thomas Hobbes, 1655 
PGP: finger schachte at  
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