So, you wanted to keep reading from STDIN for sake of easy checking with different inputs. In that case, it is smart to use the debugging capabilities of CGI.pm. 
use CGI qw(:debug);
chomp (my $choice = param('choice'));

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In reply to Re^5: CGI, STDIN and chomp problem: bug? (input) by daxim
in thread CGI, STDIN and chomp problem: bug? by Not_a_Number

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