What's the best/preferred/Perl-ish method?

That will be subjective. However, I'd have to go with push for several reasons perhaps the strongest of which is that this is precisely what it is designed to do: append entries to arrays. If it were no better than the first approach it would not be in the language.

Has the first method advantages over the second method or vice versa? What are the advantages, if any?

I see some advantages to the second method:

  1. There is no need to specify the name of the array twice therefore the programmer is less likely to make a mistake such as extracting data from the wrong array in the RHS.
  2. The first method does a lot more stuff: extracting data from the array into a list, appending other values and then overwriting the array with the resulting list. This sounds much less efficient than a simple push which (as a guess) I would expect literally to append to the array in situ. For large arrays or many ops this might become an important consideration.
  3. push will also save you from mistakes like attempting to push to a scalar.

That said, I would definitely combine your 4 pushes into one and probably use a glob or map to avoid all the repetition.

What's the habbit in case of initial array declaration and first method: put the comma's at the back or at the front?

Not sure what you mean here, sorry.

In reply to Re: Adding items to arrays: best approach? by hippo
in thread Adding items to arrays: best approach? by geertvc

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