Usage Messages

Choose a usage message when a command is missing.

usage_messages.pl

use strict;
use warnings;

my $has_command = ;
my $status = $has_command ? "ready" : "needs-help";
my $message = $has_command ? "run command" : "usage: tool command";

print "has_command=$has_command\n";
print "status=$status\n";
print "message=$message\n";

use strict;
use warnings;

my $has_command = ;
my $status = $has_command ? "ready" : "needs-help";
my $message = $has_command ? "run command" : "usage: tool command";

print "has_command=$has_command\n";
print "status=$status\n";
print "message=$message\n";

usage-messages A usage message explains the expected command shape. Programs commonly show it when required input is missing.