You are using the constant.pm pragmatic incorrectly, and constants don't do what you think they do.

Correct syntax is, 

use constant SCROLL_X => 1;
use constant SCROLL_Y => 2;
use constant FLOW_X   => 3;
use constant FLOW_Y   => 4;

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which produces constant subs of the form sub SCROLL_X () { 1;}. The prototype is important there, because it is a hint to the perl compiler that it may optimize away the sub call by replacing it with the constant value. There is no runtime reminant of the sub or its name.

Update: As Abigail-II notes, recent constant.pm can take a hashref as argument. The syntax 

use canstant {
    SCROLL_X => 1,
    SCROLL_Y => 2,
    FLOW_X   => 3,
    FLOW_Y   => 4,
};

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is fine if older versions need not be supported.

After Compline,
Zaxo

In reply to Re: managing constants created with constant.pm by Zaxo
in thread managing constants created with constant.pm by bakunin

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