[erlang-questions] Modify a list of tuples
Richard Carlsson
richardc@REDACTED
Thu Aug 14 23:36:23 CEST 2008
Dave Bryson wrote:
> What's the best way to modify a value for a given tuple in the list
> below?
>
> I have a large list with the following type of structure:
>
> [ [{a,1},{b,2}], [{b,3},{a,4}] ]
>
> I want to preserve the structure of the list and change a value on all
> the tuples with a given key. So for example, change all the values on
> the "b" tuple so the result would be:
>
> [ [{a,1},{b,CHANGED}], [{b,CHANGED},{a,4}] ]
>
> I've tried list comprehension but can't get it to preserve the rest of
> the list.
Write a list comprehension that applies lists:keymap/3 on each
of the sublists.
/Richard
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