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
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.
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.
* match: check duplicate identifiers across list-no-order patters
* match: document that list-no-order doesn't support duplicate ids between sub-pats
* match: put duplicate id docs in a margin note between the two variants
The expander as a linklet will be instantiated once, so there's no
need to capture references in closures among functions within the
expander. Add a "static" linklet compilation mode to inline the
variable addresses that would otherwise be referenced via a closure.
Although the change is intended to speed up the expander by avoiding
some indrections, it also reduces the bytecode size of the expander.
Bitmaps that track which linklet variables are used in closures turn
out to have been about 25% of the expander's bytecode size, since the
linklet has so many definitions.
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.
Use stdout log reporting instead of stderr log reporting for status
reporting during the build, so that the status report is not
misinterpreted as an error.
The old reader used an internal option to short-circuit special-value
reading when a special value acts as a terminating "character". Expose
that shortcut by allowing 'special as an argument to
`peek-{char,byte}-or-special`, and update the reader to use it.
This commit merges changes that were developed in the "racket7" repo.
See that repo (which is no longer modified) for a more fine-grained
change history.
The commit includes experimental support for running Racket on Chez
Scheme, but that "CS" variant is not built by default.
