ramda: lens (lens, lensProp, lensPath, view, set, over)

ramda8.js

import { lensProp, lensPath, view, set, over, toUpper } from "ramda"

const me = {
  firstName: "Sébastien",
  lastName: "Nicolaïdis",
  birthDate: new Date("1979-09-13T15:00Z"),
  age: 38,
  hobbies: ["Rock climbing", "Horse riding", "Chess"],
  parents: {
    brother: {
      firstName: "Frédéric",
      lastName: "Nicolaïdis",
      birthDate: new Date("1973-09-18T04:00Z"),
      age: 44,
    },
    sister: {
      firstName: "Virginia",
      lastName: "Nicolaïdis",
      birthDate: "1975-03-23T09:32Z",
      marks: [16, 20, 17, 18],
    },
  },
}

const myNameLens = lensProp("firstName") // equals lens(prop("firstName"), assoc("firstName"))
const viewMe = view(myNameLens, me)
console.log("viewMe", viewMe)
const setMe = set(myNameLens, "Patrick", me)
console.log("setMe", setMe)

const brotherNameLens = lensPath(["parents", "brother", "firstName"])
const overBrother = over(brotherNameLens, toUpper, me)
console.log("overBrother", overBrother)

const twentyLens = lensPath(["parents", "sister", "marks", 1])
console.log("view twentyLens", view(twentyLens, me))