arity-n Wraps a function with a function of a sertain arity. Installation npm install arity-n Usage function fn(a, b, c, d) {} var arityN = require('arity-n');var newFn = arityN(fn, 3); newFn.length; // => 3 var arity4 = require('arity-n/4');var newFn = arity4(fn); newFn.length; // => 4 // Max arity is 5.var newFn = arityN(fn, 7); newFn.length; // => 4