分析牛人js版删除代码注释（状态机机制）

function on_format(id) {    var textarea = document.getElementById(id);    var text = textarea.value;    var obj = format_obj();    obj.init();    obj.g_trigraph_on = document.getElementById('format_trigraph').checked;    len = text.length;    for (var c = 0; c < len; ++c) {        obj.deal(text.substring(c, c+1));    }    obj.deal('EOF');    textarea.value = obj.g_output_string;}function format_obj() {    return {        s_normal:           0,        s_char:             1,        s_char_conv:        2,        s_string:           3,        s_string_conv:      4,        s_linecomment:      5,        s_linecomment_conv: 6,        s_comment1:         7,        s_comment:          8,        s_commented1:       9,        s_conv:             10,        s_eof:              11,        g_state:            0,        g_conv_state:       0,        g_convlinecnt:      0,        g_trigraph:         0,        g_output_string:    "",        g_trigraph_on:      1,        put:            function(c) {                this.g_output_string += c;            },        init:            function() {                this.g_state = this.s_normal;                this.g_conv_state = this.s_normal;                this.g_trigraph = 0;                this.g_output_string = ""            },        deal:            function(c) {                if (this.g_trigraph_on) {                    if (c == '?') { // trigraph pre process                        if (this.g_trigraph < 2) {                            this.g_trigraph++;                            return 0;                        }                    } else if (this.g_trigraph == 2 && c == '/') {                        c = '\\';                        this.g_trigraph = 0;                    } else if (this.g_trigraph > 0) {                        var t = this.g_trigraph;                        this.g_trigraph = 2;                        while (t--) this.deal('?');                        this.g_trigraph = 0;                    }                }                if (this.g_conv_state == this.s_conv) { // '\' at end of line                    this.g_conv_state = this.s_normal;                    if (c == '\n') {                        ++this.g_convlinecnt;                        return 0;                    } else {                        if (this.g_state == this.s_comment1) {                            this.put('/');                            while (this.g_convlinecnt) --this.g_convlinecnt, this.put("\\\n");                            this.put('\\');                            this.g_state = this.s_normal;                        } else if (this.g_state == this.s_commented1) {                            this.g_state = this.s_comment;                        }                    }                } else if (c == '\\') {                    if (this.g_state == this.s_comment1 || this.g_state == this.s_commented1) {                        this.g_conv_state = this.s_conv;                        return 0;                    }                }                switch(this.g_state) {                    case this.s_normal:                        if (c == '\"') this.g_state = this.s_string, this.put(c);                        else if (c == '\'') this.g_state = this.s_char, this.put(c);                        else if (c == '/') this.g_state = this.s_comment1, this.g_convlinecnt = 0;                        else if (c == 'EOF') this.g_state = this.s_eof;                        else this.put(c);                        break;                    case this.s_char:                        this.put(c);                        if (c == '\'') this.g_state = this.s_normal;                        else if (c == '\\') this.g_state = this.s_char_conv;                        else if (c == 'EOF') this.g_state = this.s_eof;                        break;                    case this.s_char_conv:                        this.put(c);                        this.g_state = this.s_char;                        break;                    case this.s_string:                        this.put(c);                        if (c == '\"') this.g_state = this.s_normal;                        else if (c == '\\') this.g_state = this.s_string_conv;                        else if (c == 'EOF') this.g_state = this.s_eof;                        break;                    case this.s_string_conv:                        this.put(c);                        this.g_state = this.s_string;                        break;                    case this.s_linecomment:                        if (c == '\\') this.g_state = this.s_linecomment_conv;                        else if (c == '\n') this.g_state = this.s_normal, this.put(c);                        else if (c == 'EOF') this.g_state = this.s_eof;                        break;                    case this.s_linecomment_conv:                        if (c == '\\') ;                        else if (c == 'EOF') this.g_state = this.s_eof;                        else this.g_state = this.s_linecomment;                        break;                    case this.s_comment1:                        if (c == '/') this.g_state = this.s_linecomment;                        else if (c == '*') this.g_state = this.s_comment;                        else if (c == 'EOF') this.g_state = this.s_eof;                        else {                            this.put('/');                            while (this.g_convlinecnt) --this.g_convlinecnt, this.put("\\\n");                            this.g_state = this.s_normal;                            this.deal(c);                        }                        break;                    case this.s_comment:                        if (c == '*') this.g_state = this.s_commented1;                        else if (c == 'EOF') this.g_state = this.s_eof;                        break;                    case this.s_commented1:                        if (c == '/') this.g_state = this.s_normal, this.put(' ');                        else if (c == 'EOF') this.g_state = this.s_eof;                        else this.g_state = this.s_comment;                        break;                    case this.s_eof:                        return -1;                    default:                        return -2;                }                return 0;            }    }}