Allow `syntax-local-make-definition-context` in places where the
created scope is not accumulated for stripping from `quote-syntax`.
Refine the docs to clarify those situtations.
A test for the repair exposed a problem with use-site scopes
and `quote-syntax`, so fix that, too.
Closes#2062
When `local-expand` is used for a 'module-begin context, use a fresh
binding -> definition-unreadable-symbol table for the nested
expansion. That way, the table used for the main expansion is
unchanged, and re-expanding or evaluating the expanded module will
arrive at the same unreadable symbols as the initial expansion.
The report and example are from Alexis.
The old implementation turns a single optional argument into two
arguments: the optional value and a boolean to indicate whether the
optional value is supplied.
The new expansion uses `unsafe-undefined` in place of not-supplied
arguments, in the general case. If the default-value expression is
simple enough, however, it is copied to call sites that would
otherwise supply `unsafe-undefined`. In the common case where the
default value is `#f`, for example, no run-time test is needed in the
core implementation function to check whether the default is supplied,
because a `#f` will be filled in for callers.
The performance improvement is tiny to non-existent for realistic
programs, but the simpler and reduced generated code may help in the
long run.
The repair in 385f9588f8 propagates the
must-be-bound callback too far. It shouldn't be propagated anymore after
a non-rename transformer is applied.
Closes#2048
The converstion from calling `call-with-immediate-continuation-mark`
to an internal `with-immediate-continuation-mark` form did not handler
a mutable argument variable.
Although splicing was set up for applying a composable
comtinuation to most kinds of continuations, it was not
set up right for applying a composable continaution in tail
position for a just-applied composable continuation.
Thanks to Spencer Florence for the report and example.
This commit adds a section to the reference to document how the expander
tracks information about local bindings, and it extends some
syntax-local functions to allow them to accept multiple definition
contexts instead of just one. In addition, it improves the documentation
on how first-class definition contexts interact with local-expand,
syntax-local-value, and syntax-local-bind-syntaxes, and it also
clarifies what it means to create a child definition context.
For consistently with the old expander, treat `#%app` and `#%datum`
like unbound if they're bound to a rename transformer whose identifier
does not untimately refer to macro or primitive syntactice form.
Closes#2042
Perpetuate a failure to make Windows paths behave reasonably with
path-manipulation functions.
In one case, the new implementation seemed better than the old one, so
I've changed the old implementation (by deleting code) and test cases.
The old code would split "x /y" to "\\?\REL\x " and "y", and the new
one splits to "x /" and "y"; the trailing separator is now enough to
preserve the space character, and it also preserves the directoryness
of the path. Of course, "x /" splits to 'relative and "\\?\REL\x " as
it strips away the trailing "/".
A remaining problem in both implementations: some Windows API
functions implicitly erase a trailing "." in a directory name, making
"x./y" equivalent to "x/y". The Racket path-manipulation functions
don't do that, so splitting and recombining "x./y" does not access the
same path as the original. This apparently hasn't been a problem in
practice, and there are so many terrible hacks already, so I left it
alone.
The new implementation perpetuates also the implementation mistake of
representing paths internally as byte strings. If, in some terrible
universe, I'm forced to do this again, the right choice is probably to
keep the path in a parsed form with enough information to reconstruct
the original, but with the information sorted nicely to make various
normalizations and combinations easy.
This change adjusts the way that trust is threaded through bytecode
and the code inspector. In Racket v6.x, reading bytecode would fail if
the code inspector is non-original and if the bytecode contains a
reference to an unsafe operation. Now, reading bytecode doesn't fail
for that reason, but all bytecode is marked as non-runnable (even
without references to unsafe operations) when loaded under a
non-original code inspector. A `read` operation by itself remains as
safe as ever.
This commit also disables the bytecode validator. For now, the
validate can be re-enabled with `PLT_VALIDATE_LOAD`.
Make `s-exp->fasl` generate an encoding that can be parsed by any
future version of `fasl->s-exp`. The new format does not rely on the
runtime system's bytecode writer and reader.
Some built-in bytes-converter combinations that were not
supposed to require custodian registration were neveretheless
registered, which created a small leak for some programs.
