Crate mapped_guard

A note on the implementation

This library is a workaround until mapped guards become available in the standard library and uses boxing internally.

While it's in practice likely possible to implement this more efficiently (without boxing) for many guards, this isn't safe except for mutable borrows where the documentation explicitly states they are write-through.

Structs

MappedGuard

Traits

BoxedMapped	Marker types for guards that are mapped by first being boxed (because they make no guarantees that their target reference can be detached from their location in memory.) Technically this could be anything, but the operation only really makes sense for guards, in order to return the mapping from a function.
MapGuard
TryMapGuard