Hi all,

It is my first post here. I have trouble understanding the difference between both version of my code. I am using tk for my gui. I am building an array of controls within a loop and, when I use the for loop construct, the code isn't working as expected.

my @tx_grid_frame;
my @outputEnaLpbkBut;
for (my $i = 0; $i < $self->{NUM_OF_LANE_MAX}; ++$i){
    $tx_grid_frame[$i+1][1] = $quick_tx_right_frm->Frame(-relief=>'gro
+ove', -bd=>1)->grid(-row => $i+1, -column => 1, -columnspan => 1,  -r
+owspan => 1, -sticky => 'nsew');

    #Output enable when loopback
    $outputEnaLpbkBut[$i] =  $self->{W}->Add_Chk($tx_grid_frame[$i+1][
+1], '', 'top');
    $outputEnaLpbkBut[$i] -> configure(-variable=> \${$self->{OUTPUT_E
+NA_LPBK}}[$i], -command => sub{
      print "Test $i \n";
    });
  }

[download]
When this code execute, it always print  Test 10 If I change only the for loop for foreach my $i (0..$self->{NUM_OF_LANE_MAX}-1) { then the ID of the checkbox clicked is print, i.e. if I click on the 4th checkbox, I get  Test 4 As far as I understand, there should not be any differences between the two constructs. In my case, I don't understand the difference between the two codes that makes them behave differently.
Thank you for your insights,
P.

In reply to Problem understanding why for loop won't work when foreach is working by PatGro

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