Use estraverse.Syntax
diff --git a/escodegen.js b/escodegen.js
index 5fa5b22..9c10bf7 100644
--- a/escodegen.js
+++ b/escodegen.js
@@ -65,73 +65,7 @@
     estraverse = require('estraverse');
     esutils = require('esutils');
 
-    Syntax = {
-        AssignmentExpression: 'AssignmentExpression',
-        ArrayExpression: 'ArrayExpression',
-        ArrayPattern: 'ArrayPattern',
-        ArrowFunctionExpression: 'ArrowFunctionExpression',
-        BlockStatement: 'BlockStatement',
-        BinaryExpression: 'BinaryExpression',
-        BreakStatement: 'BreakStatement',
-        CallExpression: 'CallExpression',
-        CatchClause: 'CatchClause',
-        ClassBody: 'ClassBody',
-        ClassDeclaration: 'ClassDeclaration',
-        ClassExpression: 'ClassExpression',
-        ComprehensionBlock: 'ComprehensionBlock',
-        ComprehensionExpression: 'ComprehensionExpression',
-        ConditionalExpression: 'ConditionalExpression',
-        ContinueStatement: 'ContinueStatement',
-        DirectiveStatement: 'DirectiveStatement',
-        DoWhileStatement: 'DoWhileStatement',
-        DebuggerStatement: 'DebuggerStatement',
-        EmptyStatement: 'EmptyStatement',
-        ExportBatchSpecifier: 'ExportBatchSpecifier',
-        ExportDeclaration: 'ExportDeclaration',
-        ExportSpecifier: 'ExportSpecifier',
-        ExpressionStatement: 'ExpressionStatement',
-        ForStatement: 'ForStatement',
-        ForInStatement: 'ForInStatement',
-        ForOfStatement: 'ForOfStatement',
-        FunctionDeclaration: 'FunctionDeclaration',
-        FunctionExpression: 'FunctionExpression',
-        GeneratorExpression: 'GeneratorExpression',
-        Identifier: 'Identifier',
-        IfStatement: 'IfStatement',
-        ImportDeclaration: 'ImportDeclaration',
-        ImportDefaultSpecifier: 'ImportDefaultSpecifier',
-        ImportNamespaceSpecifier: 'ImportNamespaceSpecifier',
-        ImportSpecifier: 'ImportSpecifier',
-        Literal: 'Literal',
-        LabeledStatement: 'LabeledStatement',
-        LogicalExpression: 'LogicalExpression',
-        MemberExpression: 'MemberExpression',
-        MethodDefinition: 'MethodDefinition',
-        ModuleSpecifier: 'ModuleSpecifier',
-        NewExpression: 'NewExpression',
-        ObjectExpression: 'ObjectExpression',
-        ObjectPattern: 'ObjectPattern',
-        Program: 'Program',
-        Property: 'Property',
-        ReturnStatement: 'ReturnStatement',
-        SequenceExpression: 'SequenceExpression',
-        SpreadElement: 'SpreadElement',
-        SwitchStatement: 'SwitchStatement',
-        SwitchCase: 'SwitchCase',
-        TaggedTemplateExpression: 'TaggedTemplateExpression',
-        TemplateElement: 'TemplateElement',
-        TemplateLiteral: 'TemplateLiteral',
-        ThisExpression: 'ThisExpression',
-        ThrowStatement: 'ThrowStatement',
-        TryStatement: 'TryStatement',
-        UnaryExpression: 'UnaryExpression',
-        UpdateExpression: 'UpdateExpression',
-        VariableDeclaration: 'VariableDeclaration',
-        VariableDeclarator: 'VariableDeclarator',
-        WhileStatement: 'WhileStatement',
-        WithStatement: 'WithStatement',
-        YieldExpression: 'YieldExpression'
-    };
+    Syntax = estraverse.Syntax;
 
     // Generation is done by generateExpression.
     function isExpression(node) {
diff --git a/package.json b/package.json
index 05ba8dd..bdd6051 100644
--- a/package.json
+++ b/package.json
@@ -31,7 +31,7 @@
     "url": "http://github.com/estools/escodegen.git"
   },
   "dependencies": {
-    "estraverse": "^1.9.0",
+    "estraverse": "^1.9.1",
     "esutils": "^1.1.6",
     "esprima": "^1.2.2",
     "optionator": "^0.5.0"