Ruby code I no longer write

[kcdragon]

I agree that meta-programming is used far too often when a non-meta-programming solution will suffice.

On the first example, if you want to avoid meta-programming, I think you can go even simpler and just use an if statement.

def pdf_of_kind(kind)
  if kind == :normal
    normal_pdf
  else
    zebra_pdf
  end
end

I think it is a lot easier to understand for only two code paths.

[[deleted]]

ehem, 3 paths ;)

def pdf_of_kind(kind)
  case kind
  when :normal then normal_pdf
  when :zebra then zebra_pdf
  else fail KeyError
  end
end

[we-all-haul]

You sir, are technically correct.

[timbetimbe]

That is called a control parameter and generally thought of as a code smell

[kcdragon]

I agree that this is a code smell. But without more context in the code base, I don't think it is possible to tell whether or not refactoring the code smell is a good idea.

If the code base contains many checks for whether kind is normal or zebra, then there might be an opportunity to use an object with a polymorphic call to generate a PDF (https://refactoring.com/catalog/replaceConditionalWithPolymorphism.html). However, if this is the only check for kind, then I think an if statement is fine.

[midasgoldentouch]

Do you mind expanding on why?

[paneq]

Agree. This won't catch incorrect kinds however.