Section 10.13. Simple Prompting

10.13. Simple Prompting

Always prompt for interactive input.

There are few things more frustrating than firing up a program and then sitting there waiting for it to complete its task, only to realize after a few minutes that it's actually been just sitting there too, silently waiting for you to start interacting with it:

          # The quit command is case-insensitive and may be abbreviated...     Readonly my $QUIT => qr/\A q(?:uit)? \z/ixms;     # No command entered yet...     my $cmd = $EMPTY_STR;     # Until the q[uit] command is entered...     CMD:     while ($cmd !~ $QUIT) {         # Get the next command...         $cmd = <>;         last CMD if not defined $cmd;                  # Clean it up and run it...         chomp $cmd;         execute($cmd)             or carp "Unknown command: $cmd";     }

Interactive programs should always prompt for interaction whenever they're being run interactively:

          # Until the q[uit] command is entered...      CMD:     while ($cmd !~ $QUIT) {         
# Prompt if we're running interactively...
         if (is_interactive(  )) {             print get_prompt_str(  );         }         
# Get the next command...
         $cmd = <>;         last CMD if not defined $cmd;         
# Clean it up and run it...
         chomp $cmd;         execute($cmd)             or carp "Unknown command: $cmd";     }