So, let's say, purely for the sake of argument, that I have a function like: 

sub rv (@) { reverse @_; };

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and I want to call it in this context: 
sort rv @list;

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Perl won't let me because it thinks I'm trying to use &rv as the comparison function for sort. I could say: 
sort(rv(@list));

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but that doesn't look as cool.

This works: 

sort reverse @list;

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How do get perl to treat &rv the same way?

======= (added in 2019)

This has been sitting at the back of my mind for the past seven years, and I have finally come back to it.

I wasn't clear in my original question on what I wanted to know, and as a result all the answers missed the point.

I don't want to put any of the code above in a program. I want to understand why this difference exists.

In reply to Why are my functions second-class citizens? by geary@acm.org

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