quick-lint-js

Find bugs in JavaScript programs.

E0011: character is not allowed in identifiers

JavaScript allows certain non-ASCII characters in identifiers. Some characters, including most emoji, are not allowed:

function 💩AndDie() {
  throw new Error("Not yet implemented");
}

console.log(6 × 9);

let sounds = {
  🐶: "woof",
  🐮: "moo",
  🐱: "meow",
};

To fix this error, rename your class, function, or variable:

function die() {
  throw new Error("Not yet implemented");
}

Alternatively, replace the symbols with ASCII:

console.log(6 * 9);

Alternatively, write the object key or method name as a string literal:

let sounds = {
  "🐶": "woof",
  "🐮": "moo",
  "🐱": "meow",
};

Documentation for other errors