node js模块 Node.js util模块

var util = require("util"); 
util.log("sample message"); 

var util = require("util"); 
var name = "CSS"; 
var a = 33; 

console.log(util.format("%s has %d attributes", name, a)); 

var util = require("util"); 
console.log(util.isArray([])); // true 
console.log(util.isArray({ length: 0 })); // false 
//from www..cn
console.log(util.isDate(new Date())); // true 
console.log(util.isDate({})); // false 

console.log(util.isError(new Error("This is an error"))); // true 
console.log(util.isError({ message: "I have a message" })); // false