Rust variables: Difference between revisions

From wikinotes
Line 34: Line 34:


<syntaxhighlight lang="rust">
<syntaxhighlight lang="rust">
let mut name: &str = "Alex";
let mut age: i8 = 30;
age += 1;
</syntaxhighlight>
</syntaxhighlight>
</blockquote><!-- Mutability -->
</blockquote><!-- Mutability -->

Revision as of 00:10, 7 September 2021

Assignment

let age: u8 = 200;   // typed
let age = 200u8;     // type-suffix
let age = 200;       // implied type

Literals

Literal types can be declared without assigning a type.

let float = 3.14;  // f64
let integer = 7;  // i32

Constants

Constants can be declared in any scope (including global).
constants cannot be changed once assigned.

const SALT: &str = "$6$r1ohStL5/UwpNnls";
static RETRIES: i8 = 5;

Mutability

All variables are immutable by default in rust.
You can make them mutable with the mut modifier.

let mut age: i8 = 30;
age += 1;

Introspection

TODO:

learn

// use std::any::type_name;  (todo - learn)