functions - "do ... while" loop equivalent in Mathematica

Have I missed something or is there no built-in which mimics the behaviour of do ... while loop?

I am looking for a construct that evaluates procedure once and then repeatedly evaluates it while test is not fulfilled.

I'm ended up using:

While[procedure; test, {}]

But clearly the second argument is redundant, so I have a feeling that I'm missing something. Maybe not, but I just want to be sure :)

Answer

While While[procedure; test] works, it looks very similar to While[test, procedure]. The only difference is ; vs ,. While is not the most commonly used construct, so when used like this there's a high chance of misunderstanding/misreading.

If readability/reliability is a concern (for example a collaboratively developed published package), I'd use the longer but clearer

While[True,
  procedure;
  If[Not[test], Break[]]
]

The only argument here is readability and "defensive programming" (extra effort to avoid accidental problems). Readability is subjective. If you are the only person who writes/reads the code and you get used to this use of While (and thus always pay special attention to the , vs ;) then this argument doesn't apply.

Comments

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