Chaddaï Fouché chaddai.fouche at gmail.com writes:
2008/7/22 Luke Palmer lrpalmer at gmail.com:
A little formal reasoning reveals that sequence1 = sequence2 exactly
when (=) is strict in its left argument. There are four common
monads which are _not_: Identity, Reader, Writer, State (and
Gracjan Polak wrote:
How do I reason if = for parsers is lazy in its first argument?
Well, to quote from the abstract of the paper I already mentioned
(http://citeseer.ist.psu.edu/704350.html): By testing before proving we
avoid wasting time trying to prove statements that are not valid.
I
gracjanpolak:
Chaddaï Fouché chaddai.fouche at gmail.com writes:
2008/7/22 Luke Palmer lrpalmer at gmail.com:
A little formal reasoning reveals that sequence1 = sequence2 exactly
when (=) is strict in its left argument. There are four common
monads which are _not_: Identity, Reader,
Janis Voigtlaender wrote:
How about some QuickChecking in connection with the Chasing bottoms
library (http://citeseer.ist.psu.edu/704350.html)?
Ah, finally a reference to what this curios phrase is actually about...!
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Antoine Latter aslatter at gmail.com writes:
The function runIdentity is found in Control.Monad.Identity in the
mtl package.
Thanks, I see it now! Laziness is not there!
But still... Identity is a bit special monad. What other monads need full
laziness in sequence? As far as I know IO is
Gracjan Polak wrote:
Initially I spotted this possible optimization in context of monadic parser. I
am not really sure if I need this property there or not. How do I prove this to
myself?
How about some QuickChecking in connection with the Chasing bottoms
library
On Tue, Jul 22, 2008 at 1:15 AM, Gracjan Polak [EMAIL PROTECTED] wrote:
Antoine Latter aslatter at gmail.com writes:
The function runIdentity is found in Control.Monad.Identity in the
mtl package.
But still... Identity is a bit special monad. What other monads need full
laziness in
2008/7/22 Luke Palmer [EMAIL PROTECTED]:
A little formal reasoning reveals that sequence1 = sequence2 exactly
when (=) is strict in its left argument. There are four common
monads which are _not_: Identity, Reader, Writer, State (and RWS by
extension).
Still if that makes that much of a
