adding shortcut to the ids of all the special tokens

pytorch_transformers/modeling_gpt2.py

@@ -679,13 +679,16 @@ class GPT2DoubleHeadsModel(GPT2PreTrainedModel):
 
     Examples::
 
+        import torch
+        from pytorch_transformers import GPT2Tokenizer, GPT2DoubleHeadsModel
+        
         tokenizer = GPT2Tokenizer.from_pretrained('gpt2')
         model = GPT2DoubleHeadsModel.from_pretrained('gpt2')
         tokenizer.add_special_tokens({'cls_token': '[CLS]'})  # Add a [CLS] to the vocabulary (we should train it also!)
         model.resize_token_embeddings(len(tokenizer))  # Update the model embeddings to the new vocabulary size (add a vector at the end)
         choices = ["Hello, my dog is cute [CLS]", "Hello, my cat is cute [CLS]"]
         input_ids = torch.tensor([tokenizer.encode(s) for s in choices]).unsqueeze(0)  # Batch size 1, 2 choices
-        mc_token_ids = torch.tensor([input_ids.size(-1), input_ids.size(-1)]).unsqueeze(0)  # Batch size 1
+        mc_token_ids = torch.tensor([input_ids.size(-1)])  # Batch size 1
         outputs = model(input_ids, mc_token_ids)
         lm_prediction_scores, mc_prediction_scores = outputs[:2]
 

pytorch_transformers/tests/tokenization_tests_commons.py

@@ -128,8 +128,8 @@ class CommonTestCases:
             self.assertGreater(tokens[0], tokens[1])
             self.assertGreater(tokens[-2], tokenizer.vocab_size - 1)
             self.assertGreater(tokens[-2], tokens[-3])
-            self.assertEqual(tokens[0], tokenizer.convert_tokens_to_ids(tokenizer.eos_token))
-            self.assertEqual(tokens[-2], tokenizer.convert_tokens_to_ids(tokenizer.pad_token))
+            self.assertEqual(tokens[0], tokenizer.eos_token_id)
+            self.assertEqual(tokens[-2], tokenizer.eos_token_id)
 
 
         def test_required_methods_tokenizer(self):

pytorch_transformers/tokenization_utils.py

@@ -155,6 +155,62 @@ class PreTrainedTokenizer(object):
     def additional_special_tokens(self, value):
         self._additional_special_tokens = value
 
+    @property
+    def bos_token_id(self):
+        """ Id of the beginning of sentence token in the vocabulary. Log an error if used while not having been set. """
+        if self._bos_token is None:
+            logger.error("Using bos_token, but it is not set yet.")
+        return self.convert_tokens_to_ids(self._bos_token)
+
+    @property
+    def eos_token_id(self):
+        """ Id of the end of sentence token in the vocabulary. Log an error if used while not having been set. """
+        if self._eos_token is None:
+            logger.error("Using eos_token, but it is not set yet.")
+        return self.convert_tokens_to_ids(self._eos_token)
+
+    @property
+    def unk_token_is(self):
+        """ Id of the unknown token in the vocabulary. Log an error if used while not having been set. """
+        if self._unk_token is None:
+            logger.error("Using unk_token, but it is not set yet.")
+        return self.convert_tokens_to_ids(self._unk_token)
+
+    @property
+    def sep_token_id(self):
+        """ Id of the separation token in the vocabulary. E.g. separate context and query in an input sequence. Log an error if used while not having been set. """
+        if self._sep_token is None:
+            logger.error("Using sep_token, but it is not set yet.")
+        return self.convert_tokens_to_ids(self._sep_token)
+
+    @property
+    def pad_token_id(self):
+        """ Id of the padding token in the vocabulary. Log an error if used while not having been set. """
+        if self._pad_token is None:
+            logger.error("Using pad_token, but it is not set yet.")
+        return self.convert_tokens_to_ids(self._pad_token)
+
+    @property
+    def cls_token_id(self):
+        """ Id of the classification token in the vocabulary. E.g. to extract a summary of an input sequence leveraging self-attention along the full depth of the model. Log an error if used while not having been set. """
+        if self._cls_token is None:
+            logger.error("Using cls_token, but it is not set yet.")
+        return self.convert_tokens_to_ids(self._cls_token)
+
+    @property
+    def mask_token_id(self):
+        """ Id of the mask token in the vocabulary. E.g. when training a model with masked-language modeling. Log an error if used while not having been set. """
+        if self._mask_token is None:
+            logger.error("Using mask_token, but it is not set yet.")
+        return self.convert_tokens_to_ids(self._mask_token)
+
+    @property
+    def additional_special_tokens_ids(self):
+        """ Ids of all the additional special tokens in the vocabulary (list of integers). Log an error if used while not having been set. """
+        if self._additional_special_tokens is None:
+            logger.error("Using additional_special_tokens, but it is not set yet.")
+        return self.convert_tokens_to_ids(self._additional_special_tokens)
+
     def __init__(self, max_len=None, **kwargs):
         self._bos_token = None
         self._eos_token = None