Generalize splitting of `(let-values ([(x ...) (values e ...)]) ....)'
to `(let ([x e] ...) ....)' for any `e', since it's always equivalent.
Right?
(The old requirements on the `e's seem to be needed only for
`letrec-values' splitting and maybe mutable variables.)
Treat unsafe functional operations (which never raise an
exception) as omitable, which means that simple `let-values'
combinations can be split into `let' bindings, etc.
Basically, Racklog (and all versions of schelog) implement ! by
causing the failure continuation of the entire relation being
returned. They did not also cause the unification caused by the
relation to be un-done.
However, it is not easy to separate un-doing the local changes because
the unification just returns a failure continuation too. I had to call
that fail continuation but use state to communicate to its target that
the next clause should not be visited.
I don't know if this is correct. My test suite contains a lot of cut
tests that still pass. Erik's test passes too. But I'm not confident
that this really works.
Internally, there's a `prop:method-arity-error' property that is
used for keyword-accepting methods. The same thing could be
accomplished with `procedure->method', but the new property avoids
a wrapper. It might be nice to expose the property from `racket/base',
but that creates trouble for generating arity errors for keyword-
requiring procedures (i.e., when such a procedure is wrapped), so
keep it provate for now.
Closes PR 12982
Split out base-abbrev.rkt so that subtype is not dependent on abbrev.rkt.
Remove unused code in numeric-tower.rkt so that it is now a dependent of
abbrev.rkt, which allows the body of convenience.rkt to be merged back in.
Remove special casing for union.rkt and extraneous subtyping checks.
Remove union-maker.
conventions in 9.2.1 of the reference (altho the messages do
not yet do the extra level of indenting when a field is too
long, nor are there any field names ending in ...)
Also, fix the docs for the #:stronger argument to
make-contract, make-chaperone-contract, and make-flat-contract
Specifically, it seems like about 20% of the time (in drdr),
running the program
(let l()(l))
in DrRacket and then clicking the break button results in a state
where DrRacket's focus is not in the definitions window. I can't seem
to make this happen on my own machine and I'm not sure if this a
race-condition in the test suite or a real bug in DrRacket but it
seems minor enough (given all of the other focus-based testing that is
happening in this (and related) test suites) that I'm just going to
give up on this particular test.
A progress evt from a close input port must be initially ready,
and the primitive `peek-bytes-avail!' checks a progress evt
before checking whether the port is closed.
These changes resolve a race in `read-bytes-evt' and related evt
constructors.
