I am trying to figure out how to wrap a reference in a struct in order to create a HashSet of references. These references will all be allocated with an arena allocator, and thus will have identical lifetimes and remain stationary for their lifetimes.
My current attempt looks like:
struct HashableRef<'a, T> (&'a T); struct RefSet<'a, T> (std::collections::HashSet<HashableRef<'a,T>>);
and fails because T may not live long enough. Any suggestions?
The broader context is my fac build system, where I need to construct a graph describing files and rule needed to build them (or that they are needed to build). In addition to this graph, I want to have sets of rules that have not yet been built, files that are dirty, files I haven’t yet looked at in a given operation or or another, etc. This graph is used in a single thread, and an arena allocator looks great so far. I could instead add a unique identifier, but would rather just use the address itself and remove the obligation of creating and storing unique identifiers.