Creating an ANTLR grammar for Dart, potentially the syntax spec.

tools/spec_parser/spec_parse.dart

+#!/usr/bin/env dart
+// Copyright (c) 2017, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'dart:io';
+
+const String ClassPath = '.:/usr/share/java/antlr3-runtime.jar';
+const String MainClass = 'SpecParser';
+const String JavaExecutable = 'java';
+
+main([arguments]) {
+  for (String arg in arguments) {
+    handleResult(ProcessResult result) {
+      if (result.stderr.length != 0) {
+        print('Error parsing $arg:\n${result.stderr}');
+      }
+      print(result.stdout);
+    }
+
+    List<String> javaArguments = <String>['-cp', ClassPath, MainClass, arg];
+    Process.run(JavaExecutable, javaArguments).then(handleResult);
+  }
+}