Thanks for the added clarifications. Being quite lazy I never searched into the manuals for what a Perl constant is. I just assumed it would be the same as C. And that's why I use it often: more for (thinking) being lighter than a variable and much less for its read-only property. I did see smoke signals in forums saying that they never really use Perl constants, there is no point, but I ignored them. And so a constant is a sub with constant return value which ideally would be optimised by Perl to become more-or-less C #define.

That also explains the fact that there is no complain if I replace what Perl sees as a bareword "XYZ::CONST" with its sub equivalent "XYZ::CONST()" something like what Perlbotics suggested but without the use const.

So a Perl constant is a glorious sub and would be lighter than a variable if Perl eventually optimises it to a constant realising that it has a constant return value. And it's read-only. Great!

Now, why does it complain with Name "XYZ::PI" used only once: possible typo when I print the foreign variable (print $XYZ::PI). Doesn't the definition of "use" include write AS WELL as READ?

bw, bliako

In reply to Re^4: Importing constans and variables when "require"ing by bliako
in thread Importing constans and variables when "require"ing by bliako

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