Re: How to check if a function reference is valid or not?

On 11月28日, 下午8時36分, kra...@xxxxxxxxx (John W . Krahn) wrote:
On Wednesday 28 November 2007 04:14, Jeff Pang wrote:



for (keys %::) {
print "$_ -> $::{$_}\n" if /abc/;
}

__END__

the output is:
abcee -> *main::abcee
abc -> *main::abc

that's to say, when you say $f2 = \&abcee you have created an entry
in this script's symbol table.

Correct.

so, abcee can be anything (a hash, an
array, a scalar, a subroutine, a handler etc).

No, it is assigning a code reference so only the *main::abcee{CODE}
slot in the symbol table will be in use.

If you had said:

use vars '*abcee';

then abcee could be anything.

John
--
use Perl;
program
fulfillment

Thanks all

Howard

.

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