in reply to Re: Re: How to create a "CONSTANT"
in thread How to create a "CONSTANT"

The reference-dereference trick works even with scalars (which is clearer, IMHO: we're a printing a scalar, not a sui generis array): 
print "The value of PIE is ${ \PIE }.\n";

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Re: Re: Re: Re: How to create a "CONSTANT"
by sauoq (Abbot) on Jun 07, 2003 at 19:00 UTC

    Consider, for the heck of it, this: 

    use constant TWO => 2;  
$x = TWO; 
print "$x ${\TWO}\n";

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    Then someone comes along and changes the constant... 
    use constant TWO => qw( one three );
$x = TWO; 
print "$x ${\TWO}\n";

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    Oops. So, if you are going to do that defensively you should be a little more explicit... 
    use constant TWO => qw( one three ); 
$x = TWO; 
print "$x ${\scalar TWO}\n";

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    Sure, anyone who goes around changing constants should expect fire and brimstone to rain down on him... but it still happens. :-) 

    -sauoq
"My two cents aren't worth a dime.";
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