Simon PJ says:
Did you try "seq"?
x `seq` y
should evalute x to WHNF before returning y. If x is a pair
you may need to say
seqPair x `seq` y
where
seqPair (a,b) = a `seq` b
in order to force the components.
Simon
There's an easier way to force structures hyperstrictly. To force x to be
evaluated to normal form before computing y, write
(x==x) `seq` y
This depends on all the types occurring in x being Eq types, and also on
the implementation of == being hyperstrict when its result is true. This holds
for all derived instances, and for most programmer defined ones too. After
all, if x==x holds for any non-total x, then x==y must hold for some pair of
different values x and y, which we normally try to avoid!
I sometimes write
if x==x then y else error "I am the pope!"
but the seq form is nicer!
John Hughes
| -----Original Message-----
| From: Michael Marte [mailto:[EMAIL PROTECTED]]
|
|
|
| I am trying to process a huge bunch of large XML files in order
| to extract some data. For each XML file, a small summary (6 integers)
| is created which is kept until writing a HTML page displaying the
| results.
|
| The ghc-compiled program behaves as expected: It opens one
| XML file after
| the other but does not read a lot. After some 50 files, it
| bails out due
| to lack of heap storage.
|
| To overcome the problem, I tried to force the program to
| compute summaries
| immediately after reading the corresponding XML file. I tried
| some eager
| application ($!), some irrefutable pattern, and some
| strictness flags, but
| I did not succeed.
