Sortof. This is where we especially take advantage of vtable
flexibility. The methods of the vtable are really closures,
because that's far more convenient for custom ports.
Change the internal port representation to an object-with-vtable
representation. The syntax looks similar to the class system of
`racket/class`, but everything is first-order: no class values, no
mixins, etc. Also, the vtable can contain non-procedures (like #f for
"not supported" or a port to mean a direcirection).
Using objects will make port instaces smaller and support a
reorganization to eliminate ad hoc `data`-field extensions. It will
also replace a half-step was was in place for byte input
Along with the conversion, change the way the fast path for writing
works: When possible, expose a shared buffer and index into that
buffer.
Only byte string input ports are really converted, so far. A
compatibility layer maps the old protocol to the new one, so
conversion can continue piecewise.
Show the compile-time value that is not a procedure. While
this runs some risk of exposing details that are meant
to be private to a macro/language, a macro/language can
use an applicable structure to provide a more specific
error message. Meanwhile, showing the value is likely to
help for someone who needs to debug a macro problem.
When the desired reference is not an advertised commit, then try
pulling just a few commits --- at depth 8, 16, and 32 -- from the
"master" branch to check whether the commit can be found that way. If
not, fall back to the exhaustive search that requires a full download.
This should help with the common case that a package reference into
the Racket repo is a few commits behind the current master branch
(because the package server hasn't scanned the repo recently enough).
It's much faster to disover that the commit is within the first 32,
which is almost always is, than to download the entire repository.
Upgrading an auto install to an explicit install runs into trouble if
the auto install is in a wider scope. It doens't seem necessary to
promote already-installed packages for migration, anyway.
- Improve performance by using make-apply-contract, lifting,
fast path for dependent flat contracts.
- The positive blame party now consistently means the *macro def*
and the negative party means the *macro use*. The #:arg? argument
controls blame swapping.
Don't make expansion depend on `(system-type 'vm)`, because expansions
should be VM-inpendent. For example, distribution builds use a single
expansion and finish up from there for different Racket
implementations.
Although `raco dec` cannot yet usefully decompile Racket CS compiled
code, the underlying `zo-parse` and `zo-marshal` functions can now at
least read and re-write that format by just keeping the bytes for the
CS-specific part, and it can also now rouind-trip the machine- and
VM-independent format.
The "extension" module protocol predates the modern FFI and depends on
the C API. Since it's not supported on Racket CS, skip the check for
extension modules.
Skipping the check can reduce load time considerably. We should
consider depracting the extension protocol for traditional Racket.
