message: Clean up the lints
  Summary: One lint was suggested despite making the code slower and less readable, so ignore that. Explain why the other one doesn't apply in this situation.
diff: @@ -103,8 +103,7 @@ impl<'a> Lexer<'a> {
  /// We have just seen a newline, read how many indents we have
  /// and then set self.indent properly
  - #[allow(clippy::while_let_on_iterator)] // Buggy hint
  - #[allow(clippy::comparison_chain)] // Buggy hint
  + #[allow(clippy::while_let_on_iterator)] // Not possible as it is borrowed mutably
  fn calculate_indent(&mut self) -> Result<(), LexerError> {
  // consume tabs and spaces, output the indentation levels
  let xs = self.lexer.remainder().as_bytes();
  