File: serialization.js (click for a live demo)

// load math.js (using node.js)
const math = require('mathjs')

// serialize a math.js data type into a JSON string
const x = math.complex('2+3i')
const str1 = JSON.stringify(x)
// outputs {"mathjs":"Complex","re":2,"im":3}

// deserialize a JSON string into a math.js data type
// note that the reviver of math.js is needed for this:
const str2 = '{"mathjs":"Unit","value":5,"unit":"cm"}'
const y = JSON.parse(str2, math.json.reviver)
console.log(math.typeof(y)) // 'Unit'
console.log(y.toString()) // 5 cm

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