match lowering: Lower bindings in a predictable order #121716
Merged
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After the recent refactorings, we can now lower bindings in a truly predictable order. The order in #120214 was an improvement but not very clear. With this PR, we lower bindings from left to right, with the special case that
x @ pat
is traversed aspat @ x
(i.e.x
is lowered after any bindings inpat
).This description only applies in the absence of or-patterns. Or-patterns make everything complicated, because the binding place depends on the subpattern. Until I have a better idea I leave them to be handled in whatever weird order arises from today's code.
r? @matthewjasper