Support ADT types in type info reflection #151142
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| sym::name => { | ||
| if let Some(name) = name { | ||
| let name_place = self.allocate_str_dedup(name.as_str())?; | ||
| let ptr = self.mplace_to_ref(&name_place)?; | ||
| self.write_immediate(*ptr, &field_place)? | ||
| } else { | ||
| let (variant, _) = self.downcast(&field_place, sym::None)?; | ||
| self.write_discriminant(variant, &field_place)?; | ||
| } | ||
| } |
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I feel like I should write sym::Some discriminant for name? 🤔 Writing ptr directly seems to work, but this relies on how Option<&'static str> is underlyingly represented IIUC.
But const eval interpreter doesn't complain about this -- perhaps it should?
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the interpreter doesn't care if the value is exactly the same as if it had its discriminant written. There is some talk about SetDiscriminant needing to happen always, but it's not really important for us here, this will be fixed by whoever changes it
also irrelevant if we make the field just always have a name (rendering the index)
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library/core/src/mem/type_info.rs
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| #[non_exhaustive] | ||
| #[unstable(feature = "type_info", issue = "146922")] | ||
| pub struct Field { | ||
| /// The name of the struct. |
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could also make it non-optional and produce integer names for tuples and tuple structs
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Oh that was a typo.
could also make it non-optional and produce integer names for tuples and tuple structs
Good idea.
| sym::name => { | ||
| if let Some(name) = name { | ||
| let name_place = self.allocate_str_dedup(name.as_str())?; | ||
| let ptr = self.mplace_to_ref(&name_place)?; | ||
| self.write_immediate(*ptr, &field_place)? | ||
| } else { | ||
| let (variant, _) = self.downcast(&field_place, sym::None)?; | ||
| self.write_discriminant(variant, &field_place)?; | ||
| } | ||
| } |
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the interpreter doesn't care if the value is exactly the same as if it had its discriminant written. There is some talk about SetDiscriminant needing to happen always, but it's not really important for us here, this will be fixed by whoever changes it
also irrelevant if we make the field just always have a name (rendering the index)
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Tracking issue: #146922
#![feature(type_info)]This PR supports ADT types for feature
type_inforeflection.(It's still a draft PR, with implementation in progress)
Note that this PR does not take SemVer into consideration (I left a FIXME comment). As discussed earlier (comment), this requires further discussion. However, I hope we could get an initial implementation to land first, so we can start playing with it.
Progress / Checklist
mainbranch(It's currently based on PR Support primitives in type info reflection #151123, so here's an extra commit)r? @oli-obk