[erlang-questions] Lists Comprehension issue?

[Carlos Suarez Fontalvo]

Thank you.

On Wednesday, January 14, 2015, Bob Ippolito <bob@REDACTED> wrote:

> 20 is not a list of lists.
>
> On Wednesday, January 14, 2015, Carlos Suarez Fontalvo <
> eng.carlos.suarez@REDACTED
> <javascript:_e(%7B%7D,'cvml','eng.carlos.suarez@REDACTED');>> wrote:
>
>> Hi. I've reading this documentation:
>> http://www.erlang.org/doc/programming_examples/list_comprehensions.html
>>
>> And it says that
>>
>> 3.5  Simplifications with List Comprehensions
>>
>> As an example, list comprehensions can be used to simplify some of the
>> functions in lists.erl:
>>
>> append(L)   ->  [X || L1 <- L, X <- L1].
>> map(Fun, L) -> [Fun(X) || X <- L].
>> filter(Pred, L) -> [X || X <- L, Pred(X)].
>>
>> However when I tried to test this first example "append" doing something simple like this:
>>
>> 73> [X || L1 <- 20, X <- L1].
>> ** exception error: bad generator 20
>>
>> I got a "exception error" message. Any idea why?. Am I not considering something?
>>
>> Thanks in advance
>>
>>
>>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://erlang.org/pipermail/erlang-questions/attachments/20150114/ceb8558a/attachment.htm>