fn advance(&mut self) -> char {
        let ch = self.indices[self.current].1;
        self.current += 1;
        ch
    }
/// Advances the char 'iterator' by 1 char, returning the char
/// that was consumed. Note that this function doesn't check
/// for reaching EOF, since it's not necessary.
Advances the char 'iterator' by 1 char, returning the char
that was consumed. Note that this function doesn't check
for reaching EOF, since it's not necessary.
Advances the char ' iterator ' by 1 char returning the char that was consumed . Note that this function doesn ' t check for reaching EOF since it ' s not necessary .
fn advance(&mut self) -> char {
        let ch = self.indices[self.current].1;
        self.current += 1;
        ch
    }
fn advance ( & mut self ) -> char { let ch = self . indices [ self . current ] . 1 ; self . current += 1 ; ch }
Advances the char 'iterator' by 1 char, returning the char
that was consumed.
Advances the char ' iterator ' by 1 char returning the char that was consumed .
&mut self
&mut self