Simple Rust Mutation Relationship Diagram

Rust mutation can be somewhat confusing if you’re a beginner. It’s similar to C++ way of doing things on where to put the asterisk (*) and ampersand (&) sign in variable declaration. Moving the asterisk sign and ampersand sign makes the declaration sometimes more mutable and also can make it less mutable.

Here is a simple diagram on Rust mutation that I found on StackOverflow (SO). I can’t find the exact link to reference as this one is stored in my notes.

a: &T == const T* const a;      // can't mutate either
    mut a: &T == const T* a;            // can't mutate what is pointed to
    a: &mut T == T* const a;            // can't mutate pointer
mut a: &mut T == T* a;                  // can mutate both