fix: replace '==' with 'is' for types comparison

pylogics/helpers/misc.py

@@ -110,7 +110,7 @@ class RegexConstrainedString(str):
 
     def __new__(cls, value, *args, **kwargs):
         """Instantiate a new object."""
-        if type(value) == cls:
+        if type(value) is cls:
             return value
         else:
             inst = super(RegexConstrainedString, cls).__new__(cls, value)

pylogics/syntax/base.py

@@ -296,7 +296,7 @@ def __eq__(self, other):
         the set of instances of this class
         equal between them.
         """
-        return type(other) == type(self) and self.logic == other.logic
+        return type(other) is type(self) and self.logic == other.logic
 
     def __invert__(self) -> "Formula":
         """Negate."""
@@ -337,7 +337,7 @@ def __eq__(self, other):
         the set of instances of this class
         equal between them.
         """
-        return type(other) == type(self) and self.logic == other.logic
+        return type(other) is type(self) and self.logic == other.logic
 
     def __invert__(self) -> "Formula":
         """Negate."""

pylogics/syntax/ldl.py

@@ -135,7 +135,7 @@ def tail_formula(self) -> Formula:
     def __eq__(self, other):
         """Test equality."""
         return (
-            type(self) == type(other)
+            type(self) is type(other)
             and self.regular_expression == other.regular_expression
             and self.tail_formula == other.tail_formula
         )