Serializing with a replacer function

A replacer function can be used to filter or transform values being serialized.

const userRecords = [
  {name: "Joe", points: 14.9, level: 31.5},
  {name: "Jane", points: 35.5, level: 74.4},
  {name: "Jacob", points: 18.5, level: 41.2},
  {name: "Jessie", points: 15.1, level: 28.1},
];

// Remove names and round numbers to integers to anonymize records before sharing
const anonymousReport = JSON.stringify(userRecords, (key, value) =>
  key === 'name'
    ? undefined
    : (typeof value === 'number' ? Math.floor(value) : value)
);

This produces the following string:

'[{"points":14,"level":31},{"points":35,"level":74},{"points":18,"level":41},{"points":15,"level":28}]'

Found a mistake? Have a question or improvement idea? Let me know.

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