How do I dynamically redefine imported subroutines?

That's actually quite easy, but say is not being imported; it's not even a subroutine! say is an operator, and use feature 'say'; merely controls whether the compiler recognises it or not. (It always recognises CORE::say, though.)

Some operators can be overridden from within Perl by overriding GLOBAL::CORE::op, and some can't. The following checks whether say can be overridden this way: 

>perl -E"say defined(prototype('CORE::say')) ?'yes':'no'"
no

[download]

Its funky syntax doesn't permit it. 

say
say LIST
say FILEHANDLE LIST
say BLOCK LIST

[download]

It could be done using a CallChecker, but that involves dropping to C/XS.

In reply to Re: Redefining Imported Subs: of scope and no by ikegami
in thread Redefining Imported Subs: of scope and no by temporal

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