pub(crate) fn reserve_uppercase_letter(&mut self, desired_letter: char, span: Span) -> Ident {
        let letter = self.find_uppercase_letter(desired_letter);
        let ident = Ident::new(&letter, span);
        self.idents.insert(letter);
        ident
    }
/// Reserves an uppercase-letter [`Ident`] with the given [`Span`]
///
/// It is guaranteed that the returned identifier is different from any
/// identifier previously reserved by this method or by visiting an AST.
///
/// `desired_letter` must be an uppercase letter. It will be used as the
/// returned identifier if it is still available. Otherwise, a different
/// letter or combination of letters will be used.
Reserves an uppercase-letter [`Ident`] with the given [`Span`]
It is guaranteed that the returned identifier is different from any
identifier previously reserved by this method or by visiting an AST.

`desired_letter` must be an uppercase letter. It will be used as the
returned identifier if it is still available. Otherwise, a different
letter or combination of letters will be used.
Reserves an uppercase - letter [ ` Ident ` ] with the given [ ` Span ` ] It is guaranteed that the returned identifier is different from any identifier previously reserved by this method or by visiting an AST . ` desired_letter ` must be an uppercase letter . It will be used as the returned identifier if it is still available . Otherwise a different letter or combination of letters will be used .
pub(crate) fn reserve_uppercase_letter(&mut self, desired_letter: char, span: Span) -> Ident {
        let letter = self.find_uppercase_letter(desired_letter);
        let ident = Ident::new(&letter, span);
        self.idents.insert(letter);
        ident
    }
pub ( crate ) fn reserve_uppercase_letter ( & mut self , desired_letter : char , span : Span ) -> Ident { let letter = self . find_uppercase_letter ( desired_letter ) ; let ident = Ident :: new ( & letter , span ) ; self . idents . insert ( letter ) ; ident }
Reserves an uppercase-letter [`Ident`] with the given [`Span`]
It is guaranteed that the returned identifier is different from any
identifier previously reserved by this method or by visiting an AST.
Reserves an uppercase - letter [ ` Ident ` ] with the given [ ` Span ` ] It is guaranteed that the returned identifier is different from any identifier previously reserved by this method or by visiting an AST .
&mut self
desired_letter
char
span
Span
&mut self
desired_letter
char
span
Span