Quoting Malcolm Wallace <[EMAIL PROTECTED]>:
[EMAIL PROTECTED] writes:
Nhc didn't use to implement the M-R (maybe it does now). When
porting code to nhc this caused a few code changes. Perhaps
10 lines out of 10000 when I tried the Bluespec compiler. So
my gut feeling is that the M-R is a rare beast in practise.
I can confirm that nhc98 (and hence yhc) still does not implement
the M-R. I haven't noticed any particular performance problems in
code compiled by nhc98 that were down to a consequent loss of sharing.
(But I can't claim to have explicitly looked.) But as Lennart says,
you do get occasional type errors which mean you need to restructure
your code. Almost always, these are local bindings, e.g.:
Context required in LHS pattern
is an error emitted for code like:
do (x,y) <- something complicated and numeric
...
and the fix is
do xy <- something complicated and numeric
let x = fst xy
y = snd xy
...
As I recall, there were about 4-5 of these I needed to fix in the
entire nofib suite.
The changes I had to make were almost all simpler than that.
I just had to add a few type signatures.
(And thanks for supporting evidence from nhc. :)
-- Lennart
_______________________________________________
Haskell-prime mailing list
Haskell-prime@haskell.org
http://haskell.org/mailman/listinfo/haskell-prime
