"Michael Kelly" <[EMAIL PROTECTED]> wrote
> On Sat, Jan 11, 2003 at 02:00:58PM -0800, John W. Krahn wrote:
> > Rob Dixon wrote:
> > > "Michael Kelly" <[EMAIL PROTECTED]> wrote
> > > > # print out all the captured numbers
> > > > map{ print "$_\n"; } @numbers;
> > >
> > > Hi Michael.
> > >
> > > May I warn against using 'map' in a void context like this? It'll work,
> > > sure, but you're using it for the side-effect of evaluating the 'print'
> > > expression. map's purpose is to 'translate' one list into another, and here
> > > it is faithfully producing a list of (presumably) 'true' values to indicate
> > > print's success in outputting each array element. This list occupies memory,
> > > may be huge, and just gets discarded. Better to use 'foreach' like this:
> > >
> > > print "$_\n" foreach @numbers;
> >
> > Or just print the list that map produces.
> >
> > print map { "$_\n" } @numbers;
>
> Thanks, Rob and John. Somehow the "map in void context" discussions that
> have come up here at various times never got through to me. I should
> remember this time...
>
TMTOWTDI: use the output field separator ($, or $OUTPUT_FIELD_SEPARATOR):
$,="\n";
print @numbers;
--
Irina
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