comment on

I am rewriting some of my old one-liners that grew into oft-used utilities. Whilst doing so, I wanted to move a lot of hard-coded strings (pathnames and such) into constants at the top of the script (via the constant pragma). So, I type:

use constant CONST => {
                         foo => 'bar',
                         fiz => 'baz'
                     };

foreach (keys CONST)
{
    print "$_\n";
}
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This, of course, returned the error:

Type of arg 1 to keys must be hash (not constant item)
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"Owe," I thought, and I changed it to:

foreach (keys %{CONST})
{
    print "$_\n";
}
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This resulted in the error:

Variable "%CONST" is not imported
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Hmmmmmm....print CONST; printed HASH(0x1a9de10), which is what I expected. What I did not expect is that I could not access it.

Can someone please enlighten me? In the meantime, I guess I'll try various dereferencing combinations and read up on constant and perlref.

Thanks,
Jeremy

In reply to Accessing Constant Hashes by enoch

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