Re^2: loading modules using 'use'

Hi Monk,

Thank you so very much for the step-by-step explanation,

OK, in 2.1.1.1 you say A is loaded and compiled. So, what essentially is the difference between

A.pm
~~~~~~~~~~
package A;
require Exporter;
@ISA = (Exporter);
@EXPORT = qw(abc);

AND

A.pm
~~~~~~~~~~
package A;
BEGIN{
require Exporter;
@ISA = (Exporter);
@EXPORT = qw(abc);
}
[download]

as irrespective of wheather BEGIN is there A is loaded and compiled, when 'use A' is encountered. But the BEGIN blocks provides a significant improvement in case of circular dependency/inheritance issues. How does the BEGIN block create such a difference then.

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Re^3: loading modules using 'use' by ikegami (Patriarch) on Jul 12, 2010 at 22:20 UTC
If that's the entire file, there's essentially no difference between those two snippets. The BEGIN will affect the order in which those statements will be executed in relation to other statements in the file.	[reply]
Re^4: loading modules using 'use' by angshuman (Novice) on Jul 13, 2010 at 03:15 UTC
That was just a sample module... Lets assume its got plenty of subroutines written in it, which are also included in the @EXPORT list. Then ???	[reply]
Re^5: loading modules using 'use' by ikegami (Patriarch) on Jul 13, 2010 at 03:42 UTC
With `BEGIN`, `@EXPORT` will be initialised before the subs are compiled. Without, after.	[reply] [d/l] [select]