JavaScript · Language basics

let / const

Block-scoped declarations. Use const by default and let only when reassigning. Neither is hoisted to a usable value.

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Syntax

let count = 0; const name = "Ada";

Example

Try it

const name = "Ada";
let count = 0;
count += 1;
console.log(name, count);

Prefer const for values that never rebind. Avoid var in new code.

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