No, create a function with the 2 optional parts as input and the string $pack_template as output.

What!? What possible merit is there is creating a function to do concatenation? Perl has an operator to do that: 

 my $packed = pack PACK_TEMPLATE . (condition ? OPTIONAL_ADDITION : ''
+), @bits;

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In reply to Re^4: Factoring out common code in two methods of a class by BrowserUk
in thread Factoring out common code in two methods of a class by jvector

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