On Fri, 2009-09-04 at 19:33 -0700, Derick Eddington wrote:
> On Thu, 2009-09-03 at 23:42 +0300, Abdulaziz Ghuloum wrote:
> > [...]
> > I cannot
> > believe anybody is using the procedural layer and making the
> > rtds manually and then wanting to use pattern matching (a
> > syntactic facility) to match on those.
> 
> Pattern matching is a syntactic facility, but it's just sugar for doing
> the type- and shape-checking and destructuring and binding.  We use
> pattern matching on all sorts of first-class run-time things.

Sorry, I think I misconstrued what you meant.  I think you meant that
because the match clauses are syntactic, it doesn't make sense to have a
run-time RTD in the clause.  But ...

> [...]
> 
> If people want to create types at run-time, then I can justify needing
> to support RTDs.

Of course, the number of fields in the match clause is static and must
be the same as the number of fields of the dynamically created type.  I
don't know how that would work-out, but if people are dynamically
creating types, then I suppose, for some uses at least, they do know the
number of fields.  I could also add "..." to my matcher's record fields
pattern.

-- 
: Derick
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