This maybe monad implemented with a Proxy. This monad let's you chain method
calls without relying on a higher order then/chain/andThen function
var {Maybe} = require("./index");
function apiRequest() {
if (Math.random() < 0.5) {
return {person: {name: 'bobby', projects: [{lang: 'elixir', name: 'brute'}]}};
} else {
return {projects: []};
}
}
var lang = maybePerson.person.projects[0].lang.value
console.log(lang)Use value to return the current value. This returns the value or null.
andThen is still useful if wanting to use a function not implemented on the underlying value:
function someOp(value) {
console.log("Performing some op", value)
}
maybePerson.person.projects.andThen(projects => someOp(projects))Chaining methods together with will always return a new Maybe.
var maybeProjects = maybePerson.projects
console.log(maybePerson.value) // prints null or value
console.log(maybeProjects.value) // prints null or value
maybeProjects.andThen(value => { // only prints value if value is not null
console.log(value)
return value // value must be return if chaining is to continue
}).andThen(v => someOp(v)).andThen(v => someOtherOp(v))