message: Minor cleanup in derive(Freeze)
diff: @@ -145,24 +145,21 @@ fn extract_options(attrs: &[Attribute]) -> syn::Result<FreezeDeriveOptions> {
  attr.parse_args_with(|input: ParseStream| {
  loop {
  - let lookahead = input.lookahead1();
  - if lookahead.peek(validator) {
  + if input.parse::<validator>().is_ok() {
  if opts.validator.is_some() {
  return Err(input.error("`validator` was set twice"));
  }
  - input.parse::<validator>()?;
  input.parse::<Token![=]>()?;
  opts.validator = Some(input.parse()?);
  - } else if lookahead.peek(bounds) {
  + } else if input.parse::<bounds>().is_ok() {
  if opts.bounds.is_some() {
  return Err(input.error("`bounds` was set twice"));
  }
  - input.parse::<bounds>()?;
  input.parse::<Token![=]>()?;
  let bounds_input = input.parse::<LitStr>()?;
  opts.bounds = Some(bounds_input.parse()?);
  } else {
  - return Err(lookahead.error());
  + return Err(input.lookahead1().error());
  }
  if input.parse::<Option<Token![,]>>()?.is_none() {
  