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Variables & Mutability

In Aura, variables are used to store data that your program can manipulate. You can declare variables using the let and const keywords.

let (Mutable Variables)​

By default, variables declared with let are mutable. This means you can reassign their value after the initial declaration.

let x = 10;
print x; // 10

x = 20; // Reassignment is allowed
print x; // 20

const (Immutable Constants)​

Variables declared with const are immutable. Their value must be assigned at compile-time and cannot be changed during execution.

const PI = 3.14159;
PI = 3.14; // ❌ Compile Error: Cannot assign to constant PI

[!TIP] Use const for values that are guaranteed never to change, such as configuration values or mathematical constants. Use let for everything else.

Type Inference​

Aura features strong type inference. While you can explicitly annotate types, the compiler can usually figure out the type based on the assigned value.

let name = "Aura"; // Inferred as string
let age: number = 5; // Explicitly annotated as number (i32)

Naming Conventions​

  • Variable names must start with a letter or an underscore (_).
  • Subsequent characters can be letters, numbers, or underscores.
  • Aura uses camelCase for variables and SCREAMING_SNAKE_CASE for constants.