sub help {
   print(@_);
   print(" This is help?\n");
}

sub list {
   print("This is list\n");
}

our $commands = {
    'help' => \&help,
    'list' => \&list,
};

while (<STDIN>) {
    chomp;
    if ((my $name) = ($_ =~ /^(\w+)/)) {
        if (defined $commands->{$name}) {
            $commands->{$name}->($_);
        } else {
            print "I Don't understand $name\n";
        }
    }

}
[download]

that is pretty much what I said, but ok




"2b"||!"2b";$$_="the question"
Besides that, my code is untested unless stated otherwise.
One more: please review the article about regular expressions (do's and don'ts) I'm working on.

As it was posted only 2 minutes after yours, there's a good chance that it was submitted without gam3 having seen your post. (I know I have tendency to do more than one thing at once, so the posting time of my messages may have no direct relation to when I read the thread, especially for longer posts, or those that contain code samples that I want to verify beforehand).

I'm guessing that if there was a specific reason that someone would post a varient of someone else's code, they would make reference to it, and explain why they've decided to take the alternative approach.

print "Insert your command:";

$input = <STDIN>;

if ($input eq "help") {
  # do something
}
elsif ($input eq "other command") {
  # do something else
}
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Of course, if your commands are allowed to receive parameters,

print "Insert your command:";

$input = <STDIN>;

if ($input =~ /^help\s+(.*)/) {
  # do something
}
elsif ($input =~ /^other command\s+(.*)/) {
  # do something else
}
[download]

The parameters (the full string following the original command and any spaces after it) will be store in the special variable $1

You can even have a final condition for the case in which the inserted command was not valid:

else {
  print "'$input' is not a valid command. Type help for a full list of
+ commands.\n";
}
[download]