function reservedWordLookup()

in archived/SharedContent/js/Microsoft.WinJS/js/base.js [8268:8391]

• 105 lines of code
• 49 McCabe index (conditional complexity)

            function reservedWordLookup(identifier) {
                // Moving from a simple object literal lookup for reserved words to this
                // switch was worth a non-trivial performance increase (5-7%) as this path
                // gets taken for any identifier.
                //
                switch (identifier.charCodeAt(0)) {
                    case /*b*/98:
                        switch (identifier) {
                            case 'break':
                                return reservedWord(identifier);
                        }
                        break;

                    case /*c*/99:
                        switch (identifier) {
                            case 'case':
                            case 'catch':
                            case 'class':
                            case 'const':
                            case 'continue':
                                return reservedWord(identifier);
                        }
                        break;

                    case /*d*/100:
                        switch (identifier) {
                            case 'debugger':
                            case 'default':
                            case 'delete':
                            case 'do':
                                return reservedWord(identifier);
                        }
                        break;

                    case /*e*/101:
                        switch (identifier) {
                            case 'else':
                            case 'enum':
                            case 'export':
                            case 'extends':
                                return reservedWord(identifier);
                        }
                        break;

                    case /*f*/102:
                        switch (identifier) {
                            case 'false':
                                return tokens.falseLiteral;

                            case 'finally':
                            case 'for':
                            case 'function':
                                return reservedWord(identifier);
                        }

                        break;
                    case /*i*/105:
                        switch (identifier) {
                            case 'if':
                            case 'import':
                            case 'in':
                            case 'instanceof':
                                return reservedWord(identifier);
                        }
                        break;

                    case /*n*/110:
                        switch (identifier) {
                            case 'null':
                                return tokens.nullLiteral;

                            case 'new':
                                return reservedWord(identifier);
                        }
                        break;

                    case /*r*/114:
                        switch (identifier) {
                            case 'return':
                                return reservedWord(identifier);
                        }
                        break;

                    case /*s*/115:
                        switch (identifier) {
                            case 'super':
                            case 'switch':
                                return reservedWord(identifier);
                        }
                        break;

                    case /*t*/116:
                        switch (identifier) {
                            case 'true':
                                return tokens.trueLiteral;

                            case 'this':
                                return tokens.thisKeyword;

                            case 'throw':
                            case 'try':
                            case 'typeof':
                                return reservedWord(identifier);
                        }
                        break;

                    case /*v*/118:
                        switch (identifier) {
                            case 'var':
                            case 'void':
                                return reservedWord(identifier);
                        }
                        break;

                    case /*w*/119:
                        switch (identifier) {
                            case 'while':
                            case 'with':
                                return reservedWord(identifier);
                        }
                        break;
                }
                return;
            }