In this lesson we'll see how Ramda's path and pathOr functions can be used to safely access a deeply nested property from an object while avoiding the dreaded checks for undefined at each new property in the desired path.

 

const R = require('ramda');const {path, pathOr} = R;const acctDept = {    name: 'Accounts Payable',    location: '14th floor',    personnel: {        manager: {            fName: 'Bill',            lName: 'Lumberg',            title: 'director of stuff and things',            salary: 75000        }    }};const itDept = {    name: 'IT',    location: 'remote',    personnel: {}};// path: will return undefined if cannot find propconst getMrgLastName = path(['personnel', 'manager', 'lName']);const getMrgLastNameOrDefaultVal = pathOr('Nobody', ['personnel', 'manager', 'lName'])const res = getMrgLastName(acctDept);console.log("res:", res); // Lumbergconst res2 = getMrgLastName(itDept);const res3 = getMrgLastNameOrDefaultVal(itDept);console.log("res2:", res2); // undefinedconsole.log("res3:", res3); // Nobody