Changes between Version 6 and Version 7 of ParallelListComp


Ignore:
Timestamp:
Mar 27, 2008 9:33:48 PM (6 years ago)
Author:
simonmar@…
Comment:

rewrite the cons section

Legend:

Unmodified
Added
Removed
Modified
  • ParallelListComp

    v6 v7  
    2929 
    3030== Cons == 
    31  * Most people do not find them useful, and find the only slightly longer version using explicit zips clearer. 
    32  * Naive users can trip over them if they misplace a '`|`'. 
    33  * Limited, e.g. cannot express filters of zips, which are more common. 
    34  * In its more general forms it's hard to predict how the elements from each set of generators and filters will match up, e.g. 
    35    {{{ 
    36 [(i,j,k) | i <- [1..3], j <- [1..3] | k <- [1..9]] 
    37 }}} 
     31 * Some people do not find them useful, and find the only slightly longer version using explicit zip clearer. 
     32 * One more concept to learn (and implement), with relatively low payoff. 
     33 * Cannot express filters of zips.  If you want to filter the list returned by a parallel list comprehension, you 
     34   have to go back to using the zip form, or separately filter the result. 
     35 * Might cause confusing errors if an extra ''|'' is typed by accident. 
     36 * GHC has a more general mechanism in the form of [http://research.microsoft.com/%7Esimonpj/papers/list-comp/index.htm Comprehensive Comprehensions]