Note too the use of the comma operator in the while loop expression to get the prompt output each time through the loop.Not a highly recommended technique, but can be less ugly and more cogent than many of the alternative ways of achieving the same effect.

On *nix I usually set up my prompt outside the while loop along with another string of returns and spaces to erase the prompt once I drop out of the loop. Like this

my $prompt = q{Enter name (<Ctrl-D> to exit) : };
my $dePrompt
   = qq{\r}
   . q{ } x (length($prompt) + 2)
   . qq{\r};
while (1)
{
    print $prompt;
    last if eof STDIN;
    chomp(my $response = <STDIN>);

    # Do something with $response here ...

}
print $dePrompt;

[download]

This has the advantage of cleaning up the last prompt displayed before returning to a shell prompt or some further output from the script. It does not work so well under MS Windows as it seems you have to do <Ctrl-Z><Enter> to signal EOF and that throws a line before you can erase the prompt. Thus, you may as well dispense with the $dePrompt part of it there.

I am not sure why you do defined (my $input = <STDIN>). Will it not always be defined, even with just hitting <Enter> as $input will always contain at least a newline? Perhaps I'm missing something but I would have thought you'd only have to worry about definedness after the chomp.

Cheers,

JohnGG

In reply to Re^3: Problem in printing lastname and firstname by johngg
in thread Problem in printing lastname and firstname by Anonymous Monk

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