HTMLLexicalParser.js

    function HTMLLexicalParser(){

        function emitToken(token){
            console.log(token);
        }

        function error(){
            console.log("error");
        }


        function StartTagToken(){
        }

        function EndTagToken(){
        }

        function Attribute(){
        }
        
        var token;
        var attribute;

        //function consumeReference();

        //状态函数们……
        var dataState = function(c){
            if(c=="<") {
                return tagOpenState;
            }
            else {
                emitToken(c);
                return dataState;
            }
        };
        var tagOpenState = function tagOpenState(c){
            if(c=="/") {
                return endTagOpenState;
            }
            if(c.match(/[A-Z]/)) {
                token = new StartTagToken();
                token.name = c.toLowerCase();
                return tagNameState;
            }
            if(c.match(/[a-z]/)) {
                token = new StartTagToken();
                token.name = c;
                return tagNameState;
            }
            if(c=="?") {
                return bogusCommentState;
            }
            else {
                error();
                return dataState;
            }
        };
        var endTagOpenState = function endTagOpenState(c){
            if(c.match(/[A-Z]/)) {
                token = new EndTagToken();
                token.name = c.toLowerCase();
                return tagNameState;
            }
            if(c.match(/[a-z]/)) {
                token = new EndTagToken();
                token.name = c;
                return tagNameState;
            }
            if(c==">") {
                error();
                return dataState;
            }
            else {
                error();
                return bogusCommentState;
            }
        };
        var tagNameState = function tagNameState(c) {
            if(c.match(/[\t \f\n]/)) {
                return beforeAttributeNameState;
            }
            if(c=="/") {
                return selfClosingStartTagState;
            }
            if(c == ">") {
                emitToken(token);
                return dataState;
            }
            if(c.match(/[a-z]/))
            {
                token.name += c.toLowerCase();
                return tagNameState;
            }
        }
        var beforeAttributeNameState = function beforeAttributeNameState(c) {
            if(c.match(/[\t \f\n]/)) {
                return beforeAttributeNameState;
            }
            if(c=="/") {
                return selfClosingStartTagState;
            }


            if(c == ">") {
                emitToken(token);
                return dataState;
            }
            if(c.match(/[a-z]/))
            {
                attribute = new Attribute();
                attribute.name = c.toLowerCase();
                attribute.value = "";
                return attributeNameState;
            }
            if(c=="\"" || c=="'" || c=="<" || c=="\"") {
                error();
            }
            else {
                attribute = new Attribute();
                attribute.name = c;
                attribute.value = "";
                return attributeNameState;
            }
        }
        var attributeNameState = function attributeNameState(c) {
            if(c=="/") {
                token[attribute.name] = attribute.value;
                return selfClosingStartTagState;
            }
            if(c=="/") {
                token[attribute.name] = attribute.value;
                return selfClosingStartTagState;
            }
            if(c=="=") {
                return beforeAttributeValueState;
            }
            if(c.match(/[\t \f\n]/)) {
                return afterAttributeNameState;
            }
            if(c.match(/[A-Z]/))
            {
                attribute.name += c.toLowerCase();
                return attributeNameState;
            }
            else {
                attribute.name += c;
                return attributeNameState;
            }
        }

        var afterAttributeNameState = function afterAttributeNameState(c) {
            if(c=="/") {
                token[attribute.name] = attribute.value;
                return selfClosingStartTagState;
            }
            if(c=="/") {
                token[attribute.name] = attribute.value;
                return selfClosingStartTagState;
            }
            if(c=="=") {
                return beforeAttributeValueState;
            }
            if(c.match(/[\t \f\n]/)) {
                return afterAttributeNameState;
            }
            if(c.match(/[A-Z]/))
            {
                attribute = new Attribute();
                attribute.name = c.toLowerCase();
                attribute.value = "";
                
                return attributeNameState;
            }
            else {
                attribute = new Attribute();
                attribute.name = c;
                attribute.value = "";
                return attributeNameState;
            }
        }

        var beforeAttributeValueState = function beforeAttributeValueState(c) {

            if(c=="\"") {
                return attributeValueDoubleQuoted;
            }
            if(c=="\'") {
                return attributeValueSingleQuoted;
            }

            if(c.match(/[\t \f\n]/)) {
                return beforeAttributeValueState;
            }
            else {
                attribute.value += c;
                return attributeValueUnquoted;
            }
        }
        var attributeValueDoubleQuoted = function attributeValueDoubleQuoted(c) {
            if(c=="\"") {
                token[attribute.name] = attribute.value;
                return beforeAttributeNameState;
            }
            else {
                attribute.value += c;
                return attributeValueDoubleQuoted;
            }
        }

        var attributeValueSingleQuoted = function attributeValueSingleQuoted(c) {
            if(c=="\'") {
                token[attribute.name] = attribute.value;
                return beforeAttributeNameState;
            }
            else {
                attribute.value += c;
                return attributeValueSingleQuoted;
            }
        }

        var attributeValueUnquoted = function attributeValueUnquoted(c) {
            if(c.match(/[\t \f\n]/)) {
                token[attribute.name] = attribute.value;
                return beforeAttributeNameState;
            }
            else {
                attribute.value += c;
                return attributeValueUnquoted;
            }
        }
        var selfClosingStartTagState = function selfClosingStartTagState(c) {
            if(c == ">") {
                emitToken(token);
                return dataState;
            }
        }
        var bogusCommentState = function bogusCommentState(c) {
            if(c == ">") {
                return dataState;
            }
            else {
                return bogusCommentState;
            }
        }


        var state = dataState;
        this.receiveInput = function(char) {
            //console.log(state);
            state = state(char);
        }
        
    }
    

马克