Build your own ACE Grammar

Sample Code to be highlighted:

// this is part of the AceGrammar code itself

function get_mode( grammar, DEFAULT, ace )
{
    ace = ace || $ace$;  /* pass ace reference if not already available */
    var grammar_copy = clone( grammar )
    // ace required helpers
    ,Range = ace.require('ace/range').Range
    ,WorkerClient = ace.require('ace/worker/worker_client').WorkerClient
    ,AceWorker = Class(WorkerClient, {
        constructor: function AceWorker( topLevelNamespaces, mod, classname, workerUrl ) {
            var self = this, require = ace.require, config = ace.config;
            self.$sendDeltaQueue = self.$sendDeltaQueue.bind(self);
            self.changeListener = self.changeListener.bind(self);
            self.onMessage = self.onMessage.bind(self);
            if (require.nameToUrl && !require.toUrl) require.toUrl = require.nameToUrl;

if ( !workerUrl )
            {
            if (config.get("packaged") || !require.toUrl) {
                workerUrl = workerUrl || config.moduleUrl(mod, "worker");
            } else {
                var normalizePath = self.$normalizePath;
                workerUrl = workerUrl || normalizePath(require.toUrl("ace/worker/worker.js", null, "_"));

var tlns = {};
                topLevelNamespaces.forEach(function(ns) {
                    tlns[ns] = normalizePath(require.toUrl(ns, null, "_").replace(/(\.js)?(\?.*)?$/, ""));
                });
            }
            }

try {
                self.$worker = new Worker(workerUrl);
            } catch(e) {
                if (e instanceof window.DOMException) {
                    var blob = self.$workerBlob(workerUrl);
                    var URL = window.URL || window.webkitURL;
                    var blobURL = URL.createObjectURL(blob);

self.$worker = new Worker(blobURL);
                    URL.revokeObjectURL(blobURL);
                } else {
                    throw e;
                }
            }

self.$worker.postMessage({
                load: true,
                // browser caches worker source file, even with reset/reload, try to not cache
                // https://github.com/ajaxorg/ace/issues/2730
                ace_worker_base: this_path.base + '/' + config.moduleUrl("ace/worker/json") + NOCACHE
            });

self.$worker.postMessage({
                init : true,
                tlns : tlns,
                module : mod,
                classname : classname
            });

self.callbackId = 1;
            self.callbacks = {};

self.$worker.onmessage = self.onMessage;
        }
    })
    ,FoldMode = ace.require('ace/mode/folding/fold_mode').FoldMode
    ,AceFold = Class(FoldMode, {
        constructor: function( $folder ) {
            var self = this;
            FoldMode.call( self );
            self.$findFold = $folder;
            self.$lastFold = null;
        }
        ,getFoldWidget: function( session, foldStyle, row ) {
            var fold = this.$lastFold = this.$findFold( session, foldStyle, row );
            // cache the fold to be re-used in getFoldWidgetRange
            // it is supposed that getFoldWidgetRange is called after getFoldWidget succeeds
            // on same row and with same style, so same fold should be re-used for efficiency
            return fold
                ? ("markbeginend" === foldStyle && fold.end ? "end" : "start")
                : "";
        }
        ,getFoldWidgetRange: function( session, foldStyle, row, forceMultiline ) {
            // cache the fold to be re-used in getFoldWidgetRange
            // it is supposed that getFoldWidgetRange is called after getFoldWidget succeeds
            // on same row and with same style, so same fold should be re-used for efficiency
            var fold = this.$lastFold;// this.$findFold( session, foldStyle, row );
            if ( fold ) return new Range(fold[0], fold[1], fold[2], fold[3]);
        }
    })
    ,Mode = ace.require('ace/mode/text').Mode
    ,AceMode = Class(Mode, {
        constructor: function AceMode( ) {
            var self = this;
            Mode.call( self );
            self.$id = AceMode.$id;
            self.$tokenizer = AceMode.$parser;
            // comment-toggle functionality
            self.lineCommentStart = AceMode.$parser.LC;
            self.blockComment = AceMode.$parser.BC;
            // custom, user-defined, code folding generated from grammar
            self.foldingRules = new AceFold( self.folder.bind( self ) );
        }

// custom, user-defined, syntax lint-like validation/annotations generated from grammar
        ,supportGrammarAnnotations: false
        ,createWorker: function( session ) {
            if ( !this.supportGrammarAnnotations )
            {
                clear_annotations( session, AceMode.$markers );
                return null;
            }

// add this worker as an ace custom module
            //ace.config.setModuleUrl("ace/grammar_worker", this_path.file + NOCACHE);
            var worker = new AceWorker(['ace'], "ace/grammar_worker", 'AceGrammarWorker', this_path.file + NOCACHE);
            worker.attachToDocument( session.getDocument( ) );
            // create a worker for this grammar
            worker.call('init_parser', [grammar_copy], function( ){
                // hook worker to enable error annotations
                worker.on("ace_grammar_worker_error", function( e ) {
                    var errors = e.data;
                    update_annotations( session, errors, AceMode.$markers, Range )
                });
                worker.on("ace_grammar_worker_ok", function() {
                    clear_annotations( session, AceMode.$markers );
                });
            });
            worker.on("terminate", function() {
                clear_annotations( session, AceMode.$markers );
            });
            return worker;
        }

// custom, user-defined, code folding generated from grammar
        ,supportCodeFolding: true
        ,folder: function folder( session, foldStyle, row ) {
            return !this.supportCodeFolding
            ? null
            : AceMode.$folder( session, foldStyle, row, folder.options||{} );
        }

// custom, user-defined, autocompletions generated from grammar
        ,supportAutoCompletion: true
        ,autocompleter: function autocompleter( state, session, position, prefix ) {
            return !this.supportAutoCompletion
            ? []
            : AceMode.$autocompleter( state, session, position, prefix, autocompleter.options||{} );
        }
        ,getKeywords: function( append ) {
            return []; // use getCompletions
        }
        ,getCompletions: function( state, session, position, prefix ) {
            return this.autocompleter( state, session, position, prefix );
        }

,dispose: function( ) {
            var self = this;
            self.$tokenizer = self.foldingRules = self.autocompleter = null;
            AceMode.dispose( );
        }
    });
    AceMode.$id = uuid("ace_grammar_mode");
    AceMode.$markers = AceMode.$id+'$markers';
    AceMode.$parser = new AceGrammar.Parser( parse_grammar( grammar ), DEFAULT );
    AceMode.$folder = function folder( session, foldStyle, row, options ) {
        var min_row, current_row, folder = AceMode.$parser,
            fold = folder.fold( session, row, ace );
        if ( "markbeginend" === foldStyle )
        {
            if ( fold ) { fold.start = true; fold.end = false; return fold; }
            current_row = row; min_row = MAX(0, row-200); // check up to 200 rows up for efficiency
            // try to find if any block ends on this row, backwards
            // TODO, maybe a bit slower, than direct backwards search
            while ( row > min_row && (!fold || current_row !== fold[2]) ) fold = folder.fold( session, --row, ace );
            // found end of fold, return end marker
            if ( fold && current_row === fold[2] ) { fold.start = false; fold.end = true; return fold; }
        }
        else if ( fold ) { fold.start = true; fold.end = false; return fold; }
    };
    AceMode.$autocompleter = function autocompleter( state, session, position, prefix, options ) {
        return AceMode.$parser.autocomplete( state, session, position, prefix, options, ace );
    };
    AceMode.dispose = function( ) {
        if ( AceMode.$parser ) AceMode.$parser.dispose( );
        AceMode.$parser = AceMode.$folder = AceMode.$autocompleter = AceMode.autocompleter = null;
    };
    return new AceMode( ); // object
}

Grammar (JSON format): Enable Grammar Annotations

// a partial javascript grammar in simple JSON format
{

// prefix ID for regular expressions used in the grammar
"RegExpID"                          : "RE::",

// Style model
"Style"                             : {

"comment"                      : "comment"
    ,"atom"                         : "constant"
    ,"keyword"                      : "keyword"
    ,"this"                         : "keyword"
    ,"builtin"                      : "support"
    ,"operator"                     : "operator"
    ,"identifier"                   : "identifier"
    ,"property"                     : "constant.support"
    ,"number"                       : "constant.numeric"
    ,"string"                       : "string"
    ,"regex"                        : "string.regexp"

// Lexical model
"Lex"                               : {

"comment"                      : {"type":"comment","tokens":[
                                    // line comment
                                    // start, end delims  (null matches end-of-line)
                                    [  "//",  null ],
                                    // block comments
                                    // start,  end    delims
                                    [  "/*",   "*/" ]
                                    ]}
    ,"identifier"                   : "RE::/[_A-Za-z$][_A-Za-z0-9$]*/"
    ,"this"                         : "RE::/this\\b/"
    ,"property"                     : "RE::/[_A-Za-z$][_A-Za-z0-9$]*/"
    ,"number"                       : [
                                    // floats
                                    "RE::/\\d*\\.\\d+(e[\\+\\-]?\\d+)?/",
                                    "RE::/\\d+\\.\\d*/",
                                    "RE::/\\.\\d+/",
                                    // integers
                                    // hex
                                    "RE::/0x[0-9a-fA-F]+L?/",
                                    // binary
                                    "RE::/0b[01]+L?/",
                                    // octal
                                    "RE::/0o[0-7]+L?/",
                                    // decimal
                                    "RE::/[1-9]\\d*(e[\\+\\-]?\\d+)?L?/",
                                    // just zero
                                    "RE::/0(?![\\dx])/"
                                    ]
    ,"string"                       : {"type":"escaped-block","escape":"\\","tokens":
                                    // start, end of string (can be the matched regex group ie. 1 )
                                    [ "RE::/(['\"])/",   1 ]
                                    }
    ,"regex"                        : {"type":"escaped-block","escape":"\\","tokens":
                                    // javascript literal regular expressions can be parsed similar to strings
                                    [ "/",    "RE::#/[gimy]{0,4}#" ]
                                    }
    ,"operator"                     : {"tokens":[
                                    "+", "-", "++", "--", "%", ">>", "<<", ">>>",
                                    "*", "/", "^", "|", "&", "!", "~",
                                    ">", "<", "<=", ">=", "!=", "!==",
                                    "=", "==", "===", "+=", "-=", "%=",
                                    ">>=", ">>>=", "<<=", "*=", "/=", "|=", "&="
                                    ]}
    ,"delimiter"                    : {"tokens":[
                                    "(", ")", "[", "]", "{", "}", ",", "=", ";", "?", ":",
                                    "+=", "-=", "*=", "/=", "%=", "&=", "|=", "^=", "++", "--",
                                    ">>=", "<<="
                                    ]}
    ,"atom"                         : {"autocomplete":true,"tokens":[
                                    "true", "false",
                                    "null", "undefined",
                                    "NaN", "Infinity"
                                    ]}
    ,"keyword"                      : {"autocomplete":true,"tokens":[
                                    "if", "while", "with", "else", "do", "try", "finally",
                                    "return", "break", "continue", "new", "delete", "throw",
                                    "var", "const", "let", "function", "catch", "void",
                                    "for", "switch", "case", "default", "class", "import", "yield",
                                    "in", "typeof", "instanceof"
                                    ]}
    ,"builtin"                      : {"autocomplete":true,"tokens":[
                                    "Object", "Function", "Array", "String",
                                    "Date", "Number", "RegExp", "Math", "Exception",
                                    "setTimeout", "setInterval", "parseInt", "parseFloat",
                                    "isFinite", "isNan", "alert", "prompt", "console",
                                    "window", "global", "this"
                                    ]}

// Syntax model (optional)
"Syntax"                            : {

"dot_property"                  : {"sequence":[".", "property"]}
    ,"js"                           : "comment | number | string | regex | keyword | operator | atom | (('}' | ')' | this | builtin | identifier | dot_property) dot_property*)"

// what to parse and in what order
"Parser"                            : [ ["js"] ]

}