http://www.perlmonks.org?node_id=271858


in reply to Closure on Closures

However, I believe this isn't entirely accurate as a closure in perl can be any subroutine referring to lexical variables in the surrounding lexical scopes.

I might take it a step further and say "any code." Here is an example where someone accidentally created a closure with a code assertion in a regular expression.

I also offer the following variation on your bare block example for discussion:

{ my $foo = 99; CODE: { print ++$foo, "\n" }; } goto CODE;
It isn't intuitive, but that will print "100" once and then print integers counting up from 1. Given that the storage isn't the same on subsequent entries into the bare block as it is on the first one, one might argue that it isn't a closure at all. It makes sense, however, to think of it as a closure that is created on the first entry into the bare block via the goto. Of course, that makes it impossible to initialize the data. So, it's not very useful (except maybe for obfuscations.)

-sauoq
"My two cents aren't worth a dime.";