哪些操作会造成内存泄露

function leak(){
leak= "xxx"; //leak成为一个全局变量，不会被回收
}

function bindEvent(){
var obj= document.createElement( "XXX");
obj.οnclick= function(){
//Even if it‘s a empty function
}
}

var elements={
button: document.getElementById( "button"),
image: document.getElementById( "image"),
text: document.getElementById( "text")
};
function doStuff(){
image.src= "http://some.url/image";
button.click():
console.log(text.innerHTML)
}
function removeButton(){
document.body.removeChild( document.getElementById( ‘button‘))
}

var someResouce=getData();
setInterval( function(){
var node= document.getElementById( ‘Node‘);
if(node){
node.innerHTML= JSON.stringify(someResouce)
}
}, 1000)