As soon as your out subroutine's scope is exited both of in and in2 are restored to their previous contents.

That's not a problem since he doesn't create any external references to in_2. He'd need lexicals in that case. For example, he'd need to use lexicals if the outer sub returned \&in_2.

Using lexicals doesn't help here. In addition to the more complex call syntax, using lexicals would create a memory leak if recursion was involved unless you explicitly undefed the lexical at the end of the outer sub.

In reply to Re^2: Closures and undefined subs by ikegami
in thread Closures and undefined subs by Anonymous Monk

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