include documented special methods with sphinx, correct some docstrings

Author: bygu4

doc/conf.py

@@ -300,6 +300,9 @@
 # Use type annotations for documenting the return type.
 napoleon_use_rtype = False
 
+# Include documented special methods.
+napoleon_include_special_with_doc = True
+
 # Example configuration for intersphinx: refer to the Python standard library.
 intersphinx_mapping = {'https://docs.python.org/': None}
 

pyformlang/cfg/formal_grammar.py

@@ -154,7 +154,7 @@ def to_text(self) -> str:
     def from_text(
         cls: Type[GrammarT],
         text: str,
-        start_symbol: Optional[Hashable] = Variable("S")) \
+        start_symbol: Optional[Hashable] = "S") \
             -> GrammarT:
         """Read a grammar from the given text.
 

pyformlang/objects/base_epsilon.py

@@ -21,7 +21,7 @@ def __init__(self) -> None:
         super().__init__("epsilon")
 
     def __eq__(self, other: Any) -> bool:
-        """Check if the epsilon is equal to the given object."""
+        """Checks if the epsilon is equal to the given object."""
         return isinstance(other, BaseEpsilon) \
             or not isinstance(other, FormalObject) and other in EPSILON_SYMBOLS
 

pyformlang/objects/formal_object.py

@@ -36,7 +36,7 @@ def __eq__(self, other: Any) -> bool:
         return self._is_equal_to(other) and other._is_equal_to(self)
 
     def __hash__(self) -> int:
-        """Gets the hash current formal object."""
+        """Gets the hash of current formal object."""
         if self._hash is None:
             self._hash = hash(self._value)
         return self._hash