use will let the module export its symbol table into the code where the module is used and @ISA indicates to perl to check the Exporter module for methods it can't find in the current module like import hence a code that uses a module can not import symbols from the module by default unless they are exported or have been marked as OK for exportation. This is mentioned in perldoc use and perldoc require.

@EXPORT array allows you to add other symbols to be exported.

Replying to your Re^2: loading modules using 'use' comment

where I introduce a BEGIN block. How does that help ?
Help in what sense? Well, The Begin block is run even before the rest of the module file is parsed by perl however, can you clarify a bit on what you mean by 'help'?...

Excellence is an Endeavor of Persistence. A Year-Old Monk :D .

In reply to Re: loading modules using 'use' by biohisham
in thread loading modules using 'use' by angshuman

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