Make Capability types have implied capture sets for new#25346
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| it must extend `Capability`. This makes sure we add the proper capture set to `new C` | ||
| under separate compilation without having to scan its fields. | ||
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| ## Captures of |
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Code looks good, I haven't looked at the tests closely.
Why are we dropping Separate?
| * type arguments. Charge deep capture sets of type arguments to non-reserved typevars | ||
| * to the environment. Other generic parents are represented as TypeApplys, where the | ||
| * same check is already done in the TypeApply. | ||
| * 6. Check that capture sets of fields are compatibe with declared extensions of |
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| * 6. Check that capture sets of fields are compatibe with declared extensions of | |
| * 6. Check that capture sets of fields are compatible with declared extensions of |
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If a class extends a Capability, it will now get a LocalCap on creation. This solves the problem that ```scala class C extends Capability val a = C() val b: C = C() ``` did two different things: `a` was pure but `b` was impure. Now they are both impure.
... where we had use capturesImpliedByFields before.
Since we now always add `any` when creating a capability class, Stateful
should no longer be a capability class. Otherwise, we could not create
an Iterator (which extends Stateful) with capture set such as `{Iterator.this, f}`.
Also: - Do allow mixing an ExclusiveCapability class with stateful as long as it does not have exclusive fields or retains exclusive capabilities otherwise - Drop restriction that a class may not extend both Stateful and SharedCapability - Update doc pages to reflect changes to Stateful and Separate
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We don't need it anymore since we add |
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If C extends Stateful, C means C^{}
If C extends Stateful and SharedCapability, C means C^{any}
If C extends Stateful and ExclusiveCapability, C means C^{any.rd}
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If a class extends a Capability, it will now get a LocalCap on creation. This
solves the problem that
did two different things:
awas pure butbwas impure. Now they are both impure.Based on #25278
Also, several other new rules around capture sets of
new, outlined on the doc page.