in reply to Why is my array getting changed?


When you use a for(each) loop in this way it edits the elements of the array in-place: 
    #!/usr/bin/perl -wl

    use strict;


    my @a = (1,2,3);
    print "@a";


    foreach (@a) {
        $_ *= 2;
    }

    print "@a";


    foreach my $item (@a) {
        $item *= 2;
    }

    print "@a";

    __END__
    Prints:

    1 2 3
    2 4 6
    4 8 12

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Here is the relevant detail from the "Foreach Loops" section of perlsyn:

If any element of LIST is an lvalue, you can modify it by modifying VAR inside the loop.

--
John.

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Re: Re: Why is my array getting changed?
by Rhose (Priest) on Aug 26, 2002 at 14:49 UTC
    Yep, what jmcnamara said! *Smiles*

    Add the following line to your code and run it... 

    #!/usr/bin/perl -w
use strict;
my @msgtime = (1029435628);
my $i;
for ( $i = 0; $i <= 2; $i++ ) {
 foreach my $timealert (@msgtime) {
  print '[',$timealert,'][',@msgtime,']',"\n";    # <--- Add me!
  $timealert = ((time - $timealert) / 60);
  print "$timealert\n";
 }
}

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