E0176: missing arrow operator for arrow function

Arrow functions have a parameter list followed by => followed by a function body. It is a syntax error to omit the =>:

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

To fix this error, write => after the parameter list:

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

Alternatively, write function before the parameter list:

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

Introduced in quick-lint-js version 0.6.0.

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