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Variable names start with a letter or underscore, followed by any combination of letters, underscores, or digits. Bool variable names may end with a ?. It must match this regular expression: [_a-zA-Z][_a-zA-Z0-9]*\??.

Some valid variable names include: _, foo345, isDone?

Variable names that end with a ? will be a bool, but the ? is not necessary.

// both of these are valid
const isDone = true;  ✅
const isDone? = true;  ✅

// this, however, is invalid
const num? = 5;  ❌

Multiple Variables

// declare and assign immediately
const x, y = 0, 1;

// assign multiple return types
f getPoint -> number, number {}
const x, y = getPoint();

// declare then set later
let x, y: number, number;
x, y = getPoint();

// class (or any object) properties
this.x, this.y = getPoint();