Recently, I've noticed a few places where anonymous subroutines have been declared for no apparent reason: 

my $function = sub {
    # ...do stuff...
};

# Call the sub
$function->('param');

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I would write the same subroutine as such: 
sub function {
    # ...do stuff...
}

# Call the sub
function('param);

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The above two code snippets appear to do exactly the same thing. But is there a subtle difference lurking there that I have overlooked? Is there a reason to write the first form instead of the second?

I don't think I have ever written a stand-alone anonymous subroutine like this. The only place I generally use anonymous subs is as a 'value' in a hash. Typically, to pass to Template to keep logic separated from display like this: 

my $vars = {
    'date'    => $date,
    'format'  => sub { return ucfirst lc $_[0]; },
};
$template->process('example.tt', $vars);

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In reply to Anonymous subroutines by Bod

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