Dart API for adding punctuations to text (#1182)

dart-api-examples/add-punctuations/bin/init.dart

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+../../vad/bin/init.dart

dart-api-examples/add-punctuations/bin/punctuations.dart

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+// Copyright (c)  2024  Xiaomi Corporation
+import 'dart:io';
+
+import 'package:args/args.dart';
+import 'package:sherpa_onnx/sherpa_onnx.dart' as sherpa_onnx;
+import './init.dart';
+
+void main(List<String> arguments) async {
+  await initSherpaOnnx();
+
+  final parser = ArgParser()..addOption('model', help: 'Path to model.onnx');
+
+  final res = parser.parse(arguments);
+  if (res['model'] == null) {
+    print(parser.usage);
+    exit(1);
+  }
+
+  final modelFile = res['model'] as String;
+  final modelConfig = sherpa_onnx.OfflinePunctuationModelConfig(
+    ctTransformer: modelFile,
+    numThreads: 1,
+    provider: 'cpu',
+    debug: false,
+  );
+
+  final config = sherpa_onnx.OfflinePunctuationConfig(model: modelConfig);
+
+  final punct = sherpa_onnx.OfflinePunctuation(config: config);
+
+  final texts = [
+    '这是一个测试你好吗How are you我很好thank you are you ok谢谢你',
+    '我们都是木头人不会说话不会动',
+    'The African blogosphere is rapidly expanding bringing more voices online in the form of commentaries opinions analyses rants and poetry',
+  ];
+
+  for (final t in texts) {
+    final textWithPunct = punct.addPunct(t);
+    print('----------');
+    print('Before: $t');
+    print('After: $textWithPunct');
+  }
+  print('----------');
+
+  punct.free();
+}