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Some(all?) compilers transform your code into something like this internally. Its called static single assignment form. https://en.wikipedia.org/wiki/Static_single_assignment_form

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Though it's true that compilers usually turn assignments into SSA, that's not really the same as what parent was referring to. Static single assignment has the same semantics as normal C-style assignments. The parent was referring to assignments that have (Erlang's) pattern match semantics.

Also, there's a simple counterexample. You can have static single assignment that has dynamic multiple assignment (e.g. within a loop construct). Under the pattern-matching semantics, evaluating the assignment (or rather the pattern match) a second time could fail, whereas an assignment always succeeds.

>"Though it's true that compilers usually turn assignments into SSA"

What is SSA here?

Static single assignment (see Wikipedia link in grandparent).

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