E0308E0308 — Mismatched Types
The expected type does not match the actual type provided.
E0384A variable is being reassigned but was not declared as mutable.
Rust variables are immutable by default. You are trying to change the value of a variable that was declared without the mut keyword.
Add the mut keyword to the variable declaration: let mut x = value. Use shadowing (re-declaring with let) if you want a new binding with a different value. Consider if the value should actually be a constant.
let x = 5;
x = 10;E0308The expected type does not match the actual type provided.
E0152A language item (#[lang = ...]) is defined more than once.
E0520Trait implementation specialization requires a nightly compiler feature.
E0728The .await keyword is used in a function that is not declared async.
E0603You are trying to access a private item from outside its module.
E0507You are trying to move a value out of a reference, which would leave the reference dangling.