fn modify_set<F>(&mut self, f: F) -> Result<()>
        where F: FnOnce(&mut Vec<Value>)
    {
        let pos = self.pos;
        let top = self.top()?;
        if let Value::Set(ref mut set) = *top {
            f(set);
            Ok(())
        } else {
            Self::stack_error("set", top, pos)
        }
    }
// Modify the stack-top set.
Modify the stack-top set.
Modify the stack - top set .
fn modify_set<F>(&mut self, f: F) -> Result<()>
        where F: FnOnce(&mut Vec<Value>)
    {
        let pos = self.pos;
        let top = self.top()?;
        if let Value::Set(ref mut set) = *top {
            f(set);
            Ok(())
        } else {
            Self::stack_error("set", top, pos)
        }
    }
fn modify_set < F > ( & mut self , f : F ) -> Result < ( ) > where F : FnOnce ( & mut Vec < Value > ) { let pos = self . pos ; let top = self . top ( ) ? ; if let Value :: Set ( ref mut set ) = * top { f ( set ) ; Ok ( ( ) ) } else { Self :: stack_error ( " " , top , pos ) } }
Modify the stack-top set.
Modify the stack - top set .
&mut self
f
F
&mut self
f
F