Re: passing arguments in a dispatch table

Here is an example of how to pass args to subs in a dispatch table. I didn't see you pass any args in your example.

my $dispatch = {
    add => sub { return $_[0] + $_[1] },
    mul => sub { return $_[0] * $_[1] },
    div => sub { return $_[0] / $_[1] }
};

print "2 + 3 = " . $dispatch->{add}->(2,3) . "\n";
print "2 * 3 = " . $dispatch->{mul}->(2,3) . "\n";
print "2 / 3 = " . $dispatch->{div}->(2,3) . "\n";
__END__
2 + 3 = 5
2 * 3 = 6
2 / 3 = 0.666666666666667
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Comment on Re: passing arguments in a dispatch table Download Code

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Re: Re: passing arguments in a dispatch table by CharlesClarkson (Curate) on Apr 28, 2002 at 06:19 UTC
You misunderstand. I was not trying to pass arguments after the dispatch table was defined. I was trying to pass arguments predefined in the dispatch table. In the example I gave `$fruit` was the argument. If I use `\&add_entry( $fruit )`, perl will run `add_entry( $fruit )` immediately and return a reference to it's return. But `$fruit` might change before `add_entry` is dispatched or between dispatched calls. The point was to define the arguments in the table not afterward. The problem was that this solution is skipped in the dipatch table examples I found online and in books. Some examples intimated that passing arguments from the table was difficult. I found the answer so easy, I thought I had missed something. HTH, Charles K. Clarkson Clarkson Energy Homes, Inc.	[reply] [d/l] [select]
Re: Re: Re: passing arguments in a dispatch table by BUU (Prior) on Apr 28, 2002 at 08:06 UTC
Whats the point of declaring args in the dispatch table again? If the args are going to change between dispatch calls, then just call the dispatch ->(@args); if they arent going to change, then define defaults in the function itself.	[reply]