The old `cast' didn't work right for a mismatch between
a pointer GCableness and the source or target types, and
it didn't work right for an GCable pointer with a non-zero
offset. While those pitfalls were documented, the first
of them definitely has been a source of bugs in code that
I wrote.
Also added `cpointer-gcable?'
Add `file-position*', which can return #f instead of raising
an exception when a port's position is unknown. Change
`make-input-port' and `make-output-port' to accept more
kinds of values as the initial position.
These changes make it possible to synchronize a port's
position with a `port-commit-peeked' action. It's ugly,
which I think reflect something broken about position
tracking in the port protocol (which seems difficult to fix
without breaking compaibility).
Providing a port instead of a reading or writing procedure
redirects the read/write to the specified port. This shortcut
is kind of a hack, but the run-time system can easily streamline
the redirection when it's exposed this way.
Using the new redirection feature reduces overhead in
`with-output-to-bytes' and `pretty-print'.
We can't disallow the creation of bad mutators without breaking
old code, but we can prevent the JIT from treating them like
good ones.
Closes PR 13062
Stream generic operations stopped working for lists
since the operations used only the generic dispatcher
instead of the real generic functions.
(Moral of this story: write more tests)
that it drops from the expansion (like define/public) by
adding them to the origin syntax property (and sometimes
to disappeared-use; see the add-decl-props function
for details on those that aren't in the origin property)
this means that check syntax will now pick them up
so they'll show up in the blue boxes in drracket
Thanks Matthew, for some helpful advice and
comments on an initial version of the commit.
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.
