dom - document not defined error javascript -

i'm learning javascript , have created html within javascript file test simple function takes in nodes parameters. keep getting 'document not defined' error. need within js file/code define document?

i tried things listed here: referenceerror: document not defined (in plain javascript)

   var div1 = document.createelement("div"); var text1 = document.createtextnode('<div id="one">some<span>node <em>contents</em> for</span>comparison</div>'); div1.appendchild(text1); document.body.appendchild(div1);  var div2 = document.createelement("div"); var text2 = document.createtextnode('<div id="two">some<span>node contents for</span>comparison</div>'); div2.appendchild(text2); document.body.appendchild(div2);   var div3 = document.createelement("div"); var text3 = document.createtextnode('<div id="one">some<span>node <strong>contents</strong> for</span>comparison</div>'); div3.appendchild(text3); document.body.appendchild(div3);  var div4 = document.createelement("div"); var text4 = document.createtextnode('<div id="four">some<span>node <em>contents</em> for</span>comparison</div>'); div4.appendchild(text4); document.body.appendchild(div4);    function nodeequivalence(node1, node2) {     var equal = false;     if (node1.innerhtml === node2.innerhtml) {         if (node1.tagname === node2.tagname) {             if (node1.type === node2.type) {                 equal = true;             }         }     }     return equal; }  console.log(nodeequivalence(div1, div4)); 

don't use innerhtml. use createtextnode or textcontent.

create html element right way:

var div = document.createelement("div"); var text = document.createtextnode("some text"); div.appendchild(text); document.body.appendchild(div); 

your function complicated compare html nodes. function

function nodeequivalence(node1, node2) {     var equal = false;     if (node1.innerhtml === node2.innerhtml) {         if (node1.tagname === node2.tagname) {             if (node1.type === node2.type) {                 equal = true;             }         }     }     return equal; } 

is easier.