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in reply to Re^2: How to create loop in perl dynamically
in thread How to create loop in perl dynamically

I tried this, $index is input
foreach(1..$index)
{
}
Here if $index =2, foreach gets created 2 times, But how do i code inside this and control loop parameters.
Please suggest
  • Comment on Re^3: How to create loop in perl dynamically

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Re^4: How to create loop in perl dynamically
by johngg (Canon) on Sep 26, 2012 at 14:31 UTC

    By default the loop variable is held in $_ but you can assign to a variable if you wish. It is not a good idea to alter loop variables inside the loop, that leads to all sorts of grief.

    $ perl -Mstrict -Mwarnings -E '
> foreach my $outer ( 1 .. 3 )
> {
>     foreach my $inner ( 7 .. 9 )
>     {
>         say qq{$outer x $inner = @{ [ $outer * $inner ] }};
>     }
> }'
1 x 7 = 7
1 x 8 = 8
1 x 9 = 9
2 x 7 = 14
2 x 8 = 16
2 x 9 = 18
3 x 7 = 21
3 x 8 = 24
3 x 9 = 27
$

    [download]

    I hope this is helpful.

    Cheers,

    JohnGG

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Re^4: How to create loop in perl dynamically
by sundialsvc4 (Abbot) on Sep 26, 2012 at 15:52 UTC
    foreach my $foo (1 .. $x) ... creates a local variable named $foo which contains the current index for this particular loop.   Never use $_ for this purpose, usually.

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