in reply to modify the contents of an array

I think this will help you

@arr = ('092205', '092305', '092605');

map {s/^(\d{2})(\d{2})(\d{2})/$1\/$2\/$3/} @arr;

$" ="\n";
print "@arr";

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Prasad

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Re^2: modify the contents of an array
by blazar (Canon) on Sep 29, 2005 at 11:34 UTC
    No it won't. It will print the return values of those s///'s which happens to be 1.

    Also from perlstyle: 

    Avoid using grep() (or map()) or `backticks` in a void context,
that is, when you just throw away their return values.  Those func-
tions all have return values, so use them.  Otherwise use a fore-
ach() loop or the system() function instead.

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      You would be right if prasadbabu had written: 
      @arr = map {s/^(\d{2})(\d{2})(\d{2})/$1\/$2\/$3/} @arr;

      [download]
      But he didn't. He rightly ignored the return values of s/// (if you write s/^(\d{2})(\d{2})(\d{2})/$1\/$2\/$3/ for @arr, you are ignoring the return value of s/// just as much as when using map in void context), and went of the side effects of s/// - the main feature of s///.
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        You're perfectly right. I overlooked that. Hence here are my partial apologies to prasadbabu. Partial, because map still isn't the best tool for that task.
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      blazar you are absolutely right. But the above coding works for me, i tested and then only posted.

      Hereafter i try to avoid these kind of mistakes.

      Prasad

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Re^2: modify the contents of an array
by wolfger (Deacon) on Sep 30, 2005 at 12:58 UTC

    I'd have used foreach instead of map, but other than that... nice simple solution.

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