function API: function.prototype

The prototype property - the place to add shared functionality

WHEN defining the prototype on a function THEN the instance of that function inherits these properties

const fn = function() {} fn.prototype = { solution: 42, }; const obj = new fn(); assert.equal(obj.solution, 42);

Links

spec docs The very first version of the spec defines this property already, the ES1 spec, see section 15.3.5.2 (PDF 732kB).