Cleaned up std::any.
#12667
Cleaned up std::any.
#12667
Conversation
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LGTM. A bench would be nice, but not required. |
| @@ -39,12 +40,6 @@ pub enum Void { } | |||
| pub trait Any { | |||
| /// Get the `TypeId` of `self` | |||
| fn get_type_id(&self) -> TypeId; | |||
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| /// Get a void pointer to `self` | |||
| fn as_void_ptr(&self) -> *Void; | |||
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As explained in the PR description, they existed only to reliably get a pointer to self in a time with managed headers in some owned boxes.
Furthermore, they polluted the global namespace if you use Any, as every type suddenly gets a as_[mut_]void_ptr() method for something that should only be an implementatin detail.
Finally, their usage meant un-erasing a type from an Any trait object needing two virtual calls, instead of just one.
| pub unsafe fn repr_of<T>(t: &T) -> TraitObject { | ||
| cast::transmute_copy(t) | ||
| } | ||
| } |
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I'm ok with the addition of a TraitObject struct, but this method seems like it may be excessively unsafe. You have no guarantee that T is a trait object.
Perhaps this should just add the TraitObject type and you can transmute to that?
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Yeah, on second though that'd be probably better.
- Added `TraitObject` representation to `std::raw`. - Added doc to `std::raw`. - Removed `Any::as_void_ptr()` and `Any::as_mut_void_ptr()` methods as they are uneccessary now after the removal of headers on owned boxes. This reduces the number of virtual calls needed. - Made the `..Ext` implementations work directly with the repr of a trait object. - Removed `Any`-related traits from the prelude. - Added bench for `Any`
- Added `TraitObject` representation to `std::raw`. - Added doc to `std::raw`. - Removed `Any::as_void_ptr()` and `Any::as_mut_void_ptr()` methods as they are uneccessary now after the removal of headers on owned boxes. This reduces the number of virtual calls needed from 2 to 1. - Made the `..Ext` implementations work directly with the repr of a trait object. - Removed `Any`-related traits from the prelude. - Added bench. Bench before/after: ~~~ 7 ns/iter (+/- 0) 4 ns/iter (+/- 0) ~~~
TraitObjectrepresentation tostd::raw.std::raw.Any::as_void_ptr()andAny::as_mut_void_ptr()methods as they are uneccessary now after the removal of
headers on owned boxes. This reduces the number of virtual calls needed from 2 to 1.
..Extimplementations work directly with the repr ofa trait object.
Any-related traits from the prelude.Bench before/after: