---
title: Variables
description: Variable declarations, mutability, type annotations, and destructuring.
icon: Variable
---

```mist
let x = 42;                    // Type-inferred immutable
let mut y = 10;                // Mutable variable
i32 z = 100;                   // Explicit type annotation
str& s = "hello";              // Typed string reference
bool b = true;                 // Typed boolean
f64 f = 3.14;                  // Typed float
let (a, b) = (1, "two");      // Destructuring
let (x, (y, z)) = (1, (2, 3)); // Nested destructuring
```

Variable declarations follow either of two forms:

```mist
let <pattern> [= <expr>];
<type> <pattern> [= <expr>];
```

### Const and Static

```mist
const MAX: i32 = 100;
static NAME: str& = "hello";
```