E0063: missing operator between expression and arrow function

The left-hand side of => must be a list of parameters. It is a syntax error if the left-hand side looks like a function call:

let fs = require("fs");
let path = process.argv[2];
fs.readFile(path (err, data) => {
  console.log(data);
});

To fix this error, make the left-hand side of => valid by adding an operator (usually ,) before the parameter list:

let fs = require("fs");
let path = process.argv[2];
fs.readFile(path, (err, data) => {
  console.log(data);
});

Introduced in quick-lint-js version 0.2.0.

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