an unexpected (to me) difference between lists:map/2 and list comprehension

Bengt Kleberg <>
Wed Aug 9 07:48:39 CEST 2006


On 2006-08-08 16:02, James Hague wrote:
>> Just remember that the <- construct is a filter,
>> and the LHS is where some operation is applied
>> to the selection.
> 
> Except that you can also add filters elsewhere, like:
> 
> [X || X <- [1,2,3,4], X > 2]

<- is a special filter. the normal filters work with true/false.
<- works with match/nomatch.
so i still think it should get a special mentioning in the documentaion.


> (I honestly had no idea that the "<-" worked as a filter until I read
> this thread.)

i am happy that somebody else will not have to make the same mistake 
that i did.


bengt
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