src/basilisp/lang/reader.py
def next_token(self) -> str:
        """Advance the stream forward by one character and return the
        next token in the stream."""
        if self._idx < StreamReader.DEFAULT_INDEX:
            self._idx += 1
        else:
            c = self._stream.read(1)
            self._update_loc(c)
            self._buffer.append(c)
        return self.peek()
def next_token(self) -> str:
        """Advance the stream forward by one character and return the
        next token in the stream."""
        if self._idx < StreamReader.DEFAULT_INDEX:
            self._idx += 1
        else:
            c = self._stream.read(1)
            self._update_loc(c)
            self._buffer.append(c)
        return self.peek()
Advance the stream forward by one character and return the
        next token in the stream.