Monks,

I ran across a strange bug in the code of one of my modules, and I'm puzzled.

I use the $haveModule = eval { require Module; 1; } idiom fairly frequently, but it broke down for the Capture::Tiny module. Basically, it boils down to Capture::Tiny seemingly requiring module load via a BEGIN block in order to function without error. But I don't understand why, and it chafes me.

Here's code using Capture::Tiny that works: 

use strict; use warnings;
BEGIN { require Capture::Tiny; }
my $out = Capture::Tiny::capture { print "STDOUT output to capture"; }
+;
print "Captured STDOUT: [" . ( defined $out ? $out : 'undef' ) ."]\n";

[download]
Output: 
Captured STDOUT: [STDOUT output to capture]

[download]

By just removing the BEGIN block around require Capture::Tiny, the code now fails: 

use strict; use warnings;
require Capture::Tiny;
my $out = Capture::Tiny::capture { print "STDOUT output to capture"; }
+;
print "Captured STDOUT: [" . ( defined $out ? $out : 'undef' ) ."]\n";

[download]
Output: 
Can't call method "Capture::Tiny::capture" without a package or object
+ reference at C:\@local\@projects\@tests\test-Capture-Tiny.pl line 5.

[download]

The source for Capture::Tiny (@ http://cpan.uwinnipeg.ca/htdocs/Capture-Tiny/Capture/Tiny.pm.html) seems reasonably straight-forward, but I must be missing something.

Can someone offer an explanation for this behavior?

Thanks, in advance, for the illumination.

In reply to Why does Capture::Tiny require loading via BEGIN to successfully function? by Wyrdweaver

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