Polish inline math and duplicable/optional in auto generated doc

Author: reyoung

python/paddle/fluid/layers/layer_function_generator.py

@@ -44,6 +44,11 @@ def _type_to_str_(tp):
     return framework_pb2.AttrType.Name(tp)
 
 
+_two_dollar_pattern_ = re.compile(r"\$\$([^\$]+)\$\$")
+_single_dollar_pattern_ = re.compile(r"\$([^\$]+)\$")
+_two_bang_pattern_ = re.compile(r"!!([^!]+)!!")
+
+
 def _generate_doc_string_(op_proto):
     """
     Generate docstring by OpProto
@@ -55,22 +60,27 @@ def _generate_doc_string_(op_proto):
         str: the document string
     """
 
+    def escape_math(text):
+        return _two_bang_pattern_.sub(
+            r'$$\1$$',
+            _single_dollar_pattern_.sub(
+                r':math:`\1`', _two_dollar_pattern_.sub(r"!!\1!!", text)))
+
     if not isinstance(op_proto, framework_pb2.OpProto):
         raise TypeError("OpProto should be `framework_pb2.OpProto`")
 
     buf = cStringIO.StringIO()
-    buf.write(op_proto.comment)
+    buf.write(escape_math(op_proto.comment))
     buf.write('\nArgs:\n')
     for each_input in op_proto.inputs:
         line_begin = '    {0}: '.format(_convert_(each_input.name))
         buf.write(line_begin)
-        buf.write(each_input.comment)
+        buf.write(escape_math(each_input.comment))
         buf.write('\n')
-        buf.write(' ' * len(line_begin))
-        buf.write('Duplicable: ')
-        buf.write(str(each_input.duplicable))
-        buf.write('  Optional: ')
-        buf.write(str(each_input.dispensable))
+        if each_input.duplicable:
+            buf.write("  Duplicatable.")
+        if each_input.dispensable:
+            buf.write("  Optional.")
         buf.write('\n')
 
     skip_attrs = OpProtoHolder.generated_op_attr_names()
@@ -83,7 +93,7 @@ def _generate_doc_string_(op_proto):
         buf.write(' (')
         buf.write(_type_to_str_(each_attr.type))
         buf.write('): ')
-        buf.write(each_attr.comment)
+        buf.write(escape_math(each_attr.comment))
         buf.write('\n')
 
     if len(op_proto.outputs) != 0:
@@ -92,7 +102,7 @@ def _generate_doc_string_(op_proto):
         for each_opt in op_proto.outputs:
             if not each_opt.intermediate:
                 break
-        buf.write(each_opt.comment)
+        buf.write(escape_math(each_opt.comment))
 
     return buf.getvalue()