I just ported some code to OCaml and it was giving weird results. Not wrong just backwards. A quick inspection leads me to believe that (impure) code like Foo(x, y, z) -> Foo(r x, r y, r z) is being evaluated backwards, i.e. r z first. Is there a switch or flag to control this? Or a preprocessor to…

No, that’s hard-coded. Evaluation can also be controlled with laziness, of course.

Perhaps you need let rx = r x and ry = r y and rz = r z in Foo(rx,ry,rz).

[image] Jon_Harrop: Is there a switch or flag to control this? No. Evaluation order in OCaml is officially undefined, but de facto right-to-left. The only alternative is to let-bind your arguments to make evaluation order explicit. Cheers, Nicolas

For my money the canonical source for why it’s de facto right to left is Xavier Leroy’s masters thesis.

Evaluation order

Learning

lukstafi May 29, 2023, 6:12pm 5

I would swear it is right-to-left in bytecode only, and left-to-right in native code? Let’s google… Why are OCaml function arguments evaluated right-to-left?

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Evaluation order

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