Re: How to safely use $_ in a library function?

[ikegami]

The difference between

sub { ...; goto &foo; }

and

sub { ...; &foo; }

is that the stack is unwound before the call in the former and after the call in the latter. In other words, you are asking how to protect a variable in a lexical scope you explicitly exit before you need it.

You can't have it both ways. Either you create a scope where $_ is protected or you destroy it, but you can't do both.