Re: •Re: One liner to Check and undef hash elements

Nice! I knew there had to be a better way. Regarding problem 1, what exactly does ->() do? I know that without it, a coderef would be returned, and with it, the result is returned. But how does it work? Does it evaluate the sub on the spot or in the moment I access $hash_has_non_undef?

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•Re: Re: •Re: One liner to Check and undef hash elements by merlyn (Sage) on Apr 16, 2003 at 11:08 UTC
Yes, it evaluates the sub on the spot. I wanted a structure that had a quick exit when I found an item of interest, and returning from a subroutine was fresh on my mind because I'm teaching a llama course this week and had just finished subroutines. -- Randal L. Schwartz, Perl hacker Be sure to read my standard disclaimer if this is a reply.	[reply]
Re^3: One liner to Check and undef hash elements ( sub { .. }->() explained) by Aristotle (Chancellor) on Apr 16, 2003 at 11:20 UTC
`sub { ... }` as an expression returns a reference to an anonymous function. `->(@list);` takes a reference to an anonymous function and calls it. So what happens when you chain them is you define an anonymous function and call it on the spot, the anonymous function being lost, because you didn't save the reference anywhere. Makeshifts last the longest.	[reply]