Adds a sealing and unsealing function to attach (or detach)
seals onto a class via impersonator properties. Since these
properties override, they do not accumulate wrappers.
Calling seal multiple times will still accumulate multiple seal
values inside the property.
A sealed class cannot be instantiated and a subclass may not
add class members that match any of the sealed names in its
sealed parent.
These functions are intended for use by TR's `sealing->/c`
contract, but are parameterized over checking functions and
could be used for other purposes.
Use the given readtable more consistently to parse
delimiters in the top-level form. This change particularly
addresses problems with trying to restore the original
`(` when parsing a hash table, but allowing nested
forms to still use a different `(` mapping.
When a structure type has `prop:inpersonator-of`, follow it
when attemptng to access imperonator properties.
This change fixes a problem with `impersonate-procedure` as
reported by Scott Moore.
When using `compound-unit/infer` and similar, check the `link` clause
against each unit's static information for initialization dependencies.
Also, propagate dependency information in `define-compount-unit`.
Part of the clarification is duplicating information about numbers
and character in the documentation of `eqv?`. Since those two type
are the only special cases of `eqv?`, the duplication seems helpful
and managable.
be equal?-based contracts instead of = based contracts.
Before this change, the contract (or/c 1 2 +nan.0) was the same
contract as (or/c 1 2), because +nan.0 was the same contract as
the predicate (lambda (x) (= x +nan.0)), which is the same as
(lambda (x) #f). Now, +nan.0 and +nan.f are the only numbers
that are treated as equal?-based contracts, but this means that
(or/c 1 2 +nan.0) actually accepts +nan.0.
The handling of `for-template` imports by `namespace-attach-module`
didn't match the docs. The actual handling was to refrain from
attaching instances of a phase-0 module if the instance was reachable
only through a `for-template`. The rationale had to do with such
modules instances being created only through instantiation of
phase-1 modules, and phase-1 module instances aren't attached;
it doesn't work well that way, though, when different modules
are attached with intervening `namespace-require`s on the target
namespace.
The change includes a documentation correction. Previously and still,
only modules at the same phase as the attached module (as opposed to
the same phase or less) are instantiated in the target namespace.
Closes PR 14938
If a file or directory delete fails, try adjusting the file or directory
permissions to allow writes, then try deleting again. This process should
provide a more Unix-like experience and make programs behave more
consistently.
A new `current-force-delete-permissions` parameter provides access to
the raw native behavior.
If module M in package P imports module N from package Q,
and if N has a `lazy-require` for a module in R that is
triggered during the compilation of M, then P doesn't really
depend on R; P depends on Q, and Q depends on R, and P
shoudn't necessarily know anything about Q. At the same time,
a change to the file in R means that M must be recompiled.
So, continue to track the compilation dependency, but mark
it as "indirect" so that the package-dependency checker can
ignore the dependency.