JavaScript pipe, object oriented pipe declaration with example, pipeline

pipe.js

//Pipe definition:
  Object.defineProperty(Object.prototype, 'pipe',{
    value: function(...f){ return f.reduce((val, fun) => fun(val), this)},
    writable: true,
    configurable: true,
    enumerable: false
  });

//Easier logging to console:
  log = console.log;
  Object.prototype.log = function(){ log(this.toString())};

//Our functions for piping:
  doubleSay = x => x + ", " + x
  exclaim = x => x + "!"
  capitalize = x => x[0] = x[0].toUpperCase() + x.slice(1)

//Displaying: "Hello, hello!" in console:
  "hello"
    .pipe(doubleSay)
    .pipe(exclaim)
    .pipe(capitalize)
    .log()

//hello = "Hello, hello!"
  hello = "hello".pipe(doubleSay,exclaim,capitalize)