Getter on Object:
1. prop:
R.prop('x', {x: }); //=> 100
R.prop('x', {}); //=> undefined
2. props:
R.props(['x', 'y'], {x: , y: }); //=> [1, 2]
R.props(['c', 'a', 'b'], {b: , a: }); //=> [undefined, 1, 2]
Setter ob Object:
R.assoc('c', , {a: , b: }); //=> {a: 1, b: 2, c: 3}
Another way to use Lens:
var xLens = R.lens(R.prop('x'), R.assoc('x')); R.view(xLens, {x: , y: }); //=> 1
R.set(xLens, , {x: , y: }); //=> {x: 4, y: 2}