[Javascript Crocks] Safely Access Nested Object Properties with `propPath`
In this lesson, we’ll look at the propPath
utility function. We’ll ask for a property multiple levels deep in an object and get back a Maybe. We’ll get a Just
when the property exists at our path and a Nothing
if any part of the path is undefined
.
const propPath = require('crocks/Maybe/propPath') const user = {
username: 'tester',
email: 'test@gmail.com',
address: {
street: '111 E. West St',
city: 'Anywhere',
state: 'PA',
postalCode: '19123-4567'
}
}; const getPostalCode = propPath(['address', 'postalCode']);
const zip = getPostalCode(user).option('not available'); console.log(zip) //'19123-4567'
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