it's much faster in many cases
And much slower in other cases. Empty prototyped subs which only return a constant and are know at compile time are constant folded at compile time. Unlike variables: 
    $ perl -MO=Deparse -e 'sub CONST(){1;} my $CONST = 1; print CONST,
+ $CONST'
    sub CONST () { 1 }
    my $CONST = 1;
    print 1, $CONST;
    -e syntax OK

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I can live with modules exporting constants as subs, and I can live with modules exporting constants as variables. But I would oppose changing core modules. Errno, Fcntl and Socket export constants as subs. No need for a change.
Perl --((8:>*

In reply to Re: Import constants as scalar instead of bareword sub by Perl Mouse
in thread Import constants as scalar instead of bareword sub by powerman

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