def _bracket_exact_var(self, symbol):
        """Checks local first and then module global variables for an exact
        match to the specified symbol name."""
        if isinstance(self.element, Executable):
            if symbol in self.element.parameters:
                return self.element.parameters[symbol]            
            if symbol in self.element.members:
                return self.element.members[symbol]

        if symbol in self.element.module.members:
            return self.element.module.members[symbol]

        return None
Checks local first and then module global variables for an exact
        match to the specified symbol name.