Vec.js const Vec = require('Vec'); Vec([1, 2, 3]).f(v => v + 10).func; // [v => v + 10] Vec([1, 2, 3]).f(v => v + 10).exec; // [11, 12, 13] Vec([1, 2, 3]).f(v => v + 10).QED([11, 12, 13]); // true