[erlang-questions] how to make beautifulll code of this working code

[Roelof Wobben]

Thanks for the tip.

Op 10-8-2015 om 20:29 schreef Joe Armstrong:
> On Mon, Aug 10, 2015 at 6:09 PM, Roelof Wobben <r.wobben@REDACTED> wrote:
>> Op 10-8-2015 om 17:59 schreef Garry Hodgson:
>>> date_parts(Date) ->
>>>      [list_to_integer(N) || N <- string:tokens(Date,"-")].
>>
>> When testing I see this output:
>>
>> 2> dates:date_parts("2012-02-02").
>>   ** exception error: bad argument in function list_to_integer/1 called as
>> list_to_integer(<<"2012">>) in call from dates:'-date_parts/1-lc$^0/1-0-'/1
>> (dates.erl, line 6)
> If you're a beginner it might be helpful to not combine function calls
> but to write the code with intermediate variables like this:
>
> date_parts(Date) ->
>        L = string:tokens(Date,"-"),
>        [list_to_integer(I) || I <- L].
>
> That way you can add print statements to see what's going on
> like this:
>
> date_parts(Date) ->
>        L = string:tokens(Date,"-"),
>        io:format("L=~p~n",[L]),
>        [list_to_integer(I) || I <- L].
>
> As you become more experienced you'll omit the temporary variables
> because you'll *know* what they should be. But when you're beginning
> make each line of code do as little as possible and print the results to
> check your understanding.
>
> Poke each line into the shell to see what's happening.
>
> /Joe
>
>
>>
>> ---
>> Dit e-mailbericht is gecontroleerd op virussen met Avast antivirussoftware.
>> https://www.avast.com/antivirus
>>
>> _______________________________________________
>> erlang-questions mailing list
>> erlang-questions@REDACTED
>> http://erlang.org/mailman/listinfo/erlang-questions


---
Dit e-mailbericht is gecontroleerd op virussen met Avast antivirussoftware.
https://www.avast.com/antivirus