def char(self, c: str) -> None:
        """Parse the specified character.

        Args:
            c: One-character string.

        Raises:
            EndOfInput: If past the end of `self.input`.
            UnexpectedInput: If the next character is different from `c`.
        """
        if self.peek() == c:
            self.offset += 1
        else:
            raise UnexpectedInput(self, f"char '{c}'")
Parse the specified character.

        Args:
            c: One-character string.

        Raises:
            EndOfInput: If past the end of `self.input`.
            UnexpectedInput: If the next character is different from `c`.