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How do I get a reference to a builtin function?

by adram (Initiate)
on Mar 21, 2001 at 04:44 UTC ( #65922=categorized question: print w/replies, xml ) Need Help??
Contributed by adram on Mar 21, 2001 at 04:44 UTC
Q&A  > references


I would like to call a built-in function (in this case, uc) via a reference.
However, the following does not work.
(I suspect I'm not using the correct namespace for built-in functions.)

my %op = ( 'toupper' => \&uc, ... ); print $op{'toupper'}->($text);
I've tried UNIVERSAL::uc, CORE::uc, and CORE::GLOBAL::uc, but they all complain with something like (depending on the namespace I try to use):
Undefined subroutine &CORE::uc called at ...

Answer: How do I get a reference to a builtin function?
contributed by dws

I don't know of a way to do that. But perhaps you'd find the following solution acceptable: writing your own wrapper functions to which you can refer.

my %op = ( 'toupper' => sub { uc shift }, ... );

Answer: How do I get a reference to a builtin function?
contributed by igoryonya

I'd say:

my %op = ( 'toupper'=>sub{uc(@_)}, ... );
instead of shift

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