let

Declares a mutable local variable.

The type is inferred from the initializer, or written after a colon. A let can destructure a tuple: let (a, b) = pair;. if let and while let test a pattern instead.

fn main() {
    let count = 0;
    let name: string = "coil";
    let (x, y) = (1, 2);
    count = count + x + y;
}

See also#

• fn: Declares a function, a method, or (written in an expression) an anonymous function.
• const: Declares a binding that cannot be reassigned: a local, a module constant, or a class field that is set only by new.
• static: Declares a module-level or class-level slot shared by the whole program, or a method without self.
• readonly: A read-only view of a value: nothing reachable through it can be changed.
• if: Runs a block when a bool condition is true.
• else: Introduces the branch of an if that runs when its condition is false (or its pattern does not match).
• while: Repeats a block while a bool condition is true.
• for: Iterates over the values of an array, Vec, range, coroutine or any IntoIterator.