Good Monks warm salutations,

I am trying to require a module and use a constant and a variable from it but I get an error and a warning respectively.

This is the module:

# XYZ.pm
package XYZ;
use strict;
use warnings;
require Exporter;
our @ISA=qw/Exporter/;
our @EXPORT_OK = qw/PI CONST/;

our $PI = 3.14;
use constant CONST => 10.10;

1;

[download]

And this is how I require it:

# example.pl
use strict;
use warnings;
use lib '.'; 
require XYZ;
print "PI=".$XYZ::PI."\n";
print "CONST=".XYZ::CONST."\n";

[download]

I get an error:

Bareword "XYZ::CONST" not allowed while "strict subs" in use at exampl
+e.pl line 13.
Execution of example.pl aborted due to compilation errors.

[download]

Now, if I comment out the line using CONST then I get this warning:

Name "XYZ::PI" used only once: possible typo at example.pl line 11.
PI=3.14

[download]

I have deliberately not used XYZ->import(qw/PI CONST/); as I prefer to use the full name of variables and subs from other modules. But it makes no difference as to the warnings and errors mentioned above.

Can you please shed some light?

In reply to Importing constans and variables when "require"ing by bliako

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.