Your question was already answered, but I would like to suggest an alternative way to do your main loop: 
{    
    local $_;
    print "> ";
    chomp ($_ = <STDIN>);
    redo unless /\S/;
    next if "FALSE" eq cmd_select split ' ';
}

[download]
(If you don't like a bare block, you could put a while (1) in front of it and change the next if to a last unless).

My version of the loop doesn't use goto to break out of the loop and re-enter it, it doesn't use an explicite variable $exit, which is compared to the true value "FALSE", it uses chomp in favour of chop and it will try to execute the command 0 which your version skips, but it won't try to execute a line consisting of a space like yours. I also have eliminated to need for the variables $key and @param. I would prefer cmd_select to return a true/false value instead of "FALSE" and something else.

-- Abigail

In reply to Re: crafting a decent CLI by Abigail
in thread crafting a decent CLI by PetaMem

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