Frankly, I think I need an object, but I'm reluctant to use one or a closure. I am introducing a dispatch table as a new concept on a perl beginners mailing list (PBML on Yahoo!). The original script used @book as a global variable. I changed it to $friut for the example above.

I haven't added the response yet. I do a ton of editing before replying, so I'm still able to scrap this approach.

    Currently, I'm here:
sub process {
    my ( $choice, $book ) = @_;

    my $dispatch = {
        1   => \&search_menu,
        2   => sub { return \&edit_name($book)  },
        3   => sub { return add_entry($book)    },
        4   => sub { return delete_entry($book) },
        5   => \&save_default,
        6   => \sub{ print "Goodbye!\n"; die; },
        e   => \sub{ print "Goodbye!\n"; die; },
    };

    print &{ $dispatch->{ $choice } };
}

[download]

It's a direct move from a group of if - elsif blocks that did the same thing. That's why I'd like to call the subs the same way now. I can introduce better concepts in later posts. I consider this an intermediate approach. Later, $dispatch will be passed to process()as well (which is why I use a hash reference instead of a hash). To help with processing the search menu. $book is reference to @book initally taken from a flat file. memoize immediately comes to mind, but too many beginners shun modules and I don't want to lose my audience.

I initially scrapped an idea of using a BEGIN block. Perhaps I could combine the two and grab the array reference in each subroutine as someone else mentioned. Though I find using the dispatch table as a source for the arguments that are passed more powerful.

BEGIN {
    open FH, 'my_db' or die "Cannot open my_db: $!";
    my @book = split /,/, <FH>;
    sub address_book { return \@book }
}

[download]

HTH,
Charles K. Clarkson
Clarkson Energy Homes, Inc.

In reply to Re: Re: passing arguments in a dispatch table by CharlesClarkson
in thread passing arguments in a dispatch table by CharlesClarkson

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