Improve aperture macros doc

gerbonara/aperture_macros/expression.py

@@ -180,6 +180,9 @@ class ConstantExpression(Expression):
     
 @dataclass(frozen=True, slots=True)
 class VariableExpression(Expression):
+    ''' An expression that encapsulates some other complex expression and will replace all occurences of it with a newly
+    allocated variable at export time.
+    '''
     expr: Expression
 
     def optimized(self, variable_binding={}):
@@ -201,6 +204,7 @@ class VariableExpression(Expression):
 
 @dataclass(frozen=True, slots=True)
 class ParameterExpression(Expression):
+    ''' An expression that refers to a macro variable or parameter '''
     number: int
 
     def optimized(self, variable_binding={}):

gerbonara/aperture_macros/parse.py

@@ -93,7 +93,7 @@ class ApertureMacro:
                     name, _, expr = block.partition('=')
                     number = int(name[1:])
                     if number in variables:
-                        warnings.warn(f'Re-definition of aperture macro variable ${number} inside macro. Previous definition of ${number} was ${variables[number]}.')
+                        warnings.warn(f'Re-definition of aperture macro variable ${number} inside aperture macro "{macro_name}". Previous definition of ${number} was ${variables[number]}.')
                     variables[number] = _parse_expression(expr, variables, parameters)
                 except Exception as e:
                     raise SyntaxError(f'Error parsing variable definition {block!r}') from e