GhostCell: separating permissions from data in Rust

The Rust language offers a promising approach to safe systems programming based on the principle of aliasing XOR mutability : value may be either aliased or mutable, but not both at same time. However, implement pointer-based data structures with internal sharing, such as graphs doubly-linked lists, we need able mutate state. To support structures, provides number APIs that offer so-called interior ability via method calls shared reference. Unfortunately, existing sacrifice flexibility, concurrent access, and/or performance, in exchange for safety. In this paper, propose new API called GhostCell which avoids sacrifices by separating permissions from it enables user safely synchronize access collection single permission. repurposes an old trick typed functional programming: branded types (as exemplified Haskell’s ST monad), combine phantom and rank-2 polymorphism simulate lightweight form state-dependent types. We have formally proven soundness adapting extending RustBelt, semantic proof representative subset Rust, mechanized Coq.