eval() is part of the standard distribution of PERL.

If you wanted to allow the program to keep running until the user exits you could use something like this:

#!/usr/bin/perl

$| = 1;

while( ) {
    print "Number, plz: ";
    $input = <>;
    chomp $input;
    print "\nOutput is: ", ( ($input*2)-1 ), "\n";
}
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That seemed to work on my system.



If you make something idiot-proof, eventually someone will make a better idiot.
I am that better idiot.