Declarations and types

Local variables

var count: i32 = 1;
var limit: i32 = 10;
var index: i32 = count + 1;

Declaration	Meaning
var	Declares a local variable whose value can be reassigned

var is the syntax for declaring local variables. Each local declaration states its type after the variable name:

var capacity: i64 = 4096;
var doubled: i64 = capacity * 2;

Use var name: Type; when declaring storage without an initializer, and var name: Type = expression; when providing an initial value.

Top-level storage declarations

const PAGE_SIZE: i32 = 4096;
static request_count: i64 = 0;

const and static are top-level declarations. Use var for locals inside function bodies.

Integer and floating-point types

Wave provides these integer and floating-point types:

• Signed: i8, i16, i32, i64, i128
• Unsigned: u8, u16, u32, u64, u128
• Pointer-sized: isz, usz
• Floating point: f32, f64

isz and usz represent signed and unsigned integers sized for the target's address space.

Other built-in types

Type	Purpose
bool	true or false
char	Character value
byte	Byte value
str	String value
ptr<T>	Pointer intended to address T
array<T, N>	Fixed-length array with element type T and length N

User-defined structs, enums, and type aliases can also appear in type positions.

Arrays

var values: array<i32, 4> = [10, 20, 30, 40];
var first: i32 = values[0];
values[1] = 25;

When an array is initialized with an array literal, the declared length must match the number of elements. Indexing uses [].

Type aliases

type UserId = u64;
var id: UserId = 7;

A type alias is a readable alternative name for another type. In this example, UserId can be used anywhere a u64 is expected.