A type-changing (map f) is the case into's single shadowed element name
would break if the shadowing were a trick rather than the language's
rule; it is not, because each stage is a fresh slot at its own type, and
into.flan now runs an i32 source into a (Vec f32) to say so.
A move-only accumulator carried round by recur is the shape BUILT.md
pitches the form on and was untested. It works, and recur.flan now
carries a Vec three times round and answers with it.
block's empty-body arm returned before the loop that distributes the
tail, so (do) in a tail position left ctx.tail set for whatever was
checked next. Latent rather than live — every consumer sets it
immediately before use, and the leaking form is always Unit-typed — but
it is one line to close and the invariant is easier to state closed.
Also the PORTING.md line listing loop/recur among the things with no
customer: it was built, and the half of that finding that still stands is
tail calls, which were not.
Joseph Ferano
0405666b1f