Mirko Rahn wrote:
apfelmus wrote:
Note that using Peano-numbers can achieve the same effect of stopping
the length calculation as soon as more than one character is different.
data Nat = Zero | Succ Nat deriving (Eq, Ord)
instance Num Nat where
(Succ x) + y = Succ (x+y)
apfelmus wrote:
Note that using Peano-numbers can achieve the same effect of stopping
the length calculation as soon as more than one character is different.
data Nat = Zero | Succ Nat deriving (Eq, Ord)
instance Num Nat where
(Succ x) + y = Succ (x+y)
Zero+ y = y
Very
Dougal Stanton wrote:
I think I will have to, sooner or later, become more versed in the
subtle ways of non-IO monads. They seem to be capable of some
seriously tricksy shenanigans.
Keep trying. At some point you will achieve enlightenment in a blinding
flash of light. Then you will write a
Dougal Stanton wrote:
I worked out that [ (a,b) | a - as, b - bs ] must be equivalent to
comp = concatMap (\x - map ((,) x) ys) xs
but I can't really say how conditions like a /= b get slotted in to
that style. Is there a reference for that?
Here's an example translation
[ (a,b) | a -
Mirko Rahn wrote:
wanted ws = [ (w,v) | (w:vs) - tails ws, v - vs, difference w v 2 ]
Moreover, we only calculate the difference to check whether it is
smaller than 2. We can do this directly (capturing the common pattern):
diff_lt_2 = diff (diff (const . const $ False))
diff _ []
Dougal Stanton wrote:
The following is a slap-dash program for generating a list of pairs of
words which differ by, at most, one letter. It's quite verbose at the
moment, because (a) that was the way I wrote it, a snippet at a time,
and (b) I lack the wit to make it shorter.
Can anyone
On 18/07/07, apfelmus [EMAIL PROTECTED] wrote:
I like it for its elegant point-free style :)
Yes, well, I am rather enamoured of them! :-)
Apparently, difference can only detect character replacements but not
character insertion or deletion, but that's probably not your use case.
Yes,
On 7/18/07, Dougal Stanton [EMAIL PROTECTED] wrote:
I worked out that [ (a,b) | a - as, b - bs ] must be equivalent to
comp = concatMap (\x - map ((,) x) ys) xs
but I can't really say how conditions like a /= b get slotted in to
that style. Is there a reference for that?
As I understand it,
On 18/07/07, J. Garrett Morris [EMAIL PROTECTED] wrote:
You're partway there - concatMap is flip (=), so you have the xs =
(\x - stuff) part.
Ah, yes! I read about this equivalence in one of the other threads
today but it didn't make any connection. Doh!
I think I will have to, sooner or
