pub fn take_safely(&mut self) -> MirRelationExpr {
        let typ = self.typ();
        std::mem::replace(
            self,
            MirRelationExpr::Constant {
                rows: Ok(vec![]),
                typ,
            },
        )
    }
/// Take ownership of `self`, leaving an empty `MirRelationExpr::Constant` with the correct type.
Take ownership of `self`, leaving an empty `MirRelationExpr::Constant` with the correct type.
Take ownership of ` self ` leaving an empty ` MirRelationExpr :: Constant ` with the correct type .
pub fn take_safely(&mut self) -> MirRelationExpr {
        let typ = self.typ();
        std::mem::replace(
            self,
            MirRelationExpr::Constant {
                rows: Ok(vec![]),
                typ,
            },
        )
    }
pub fn take_safely ( & mut self ) -> MirRelationExpr { let typ = self . typ ( ) ; std :: mem :: replace ( self , MirRelationExpr :: Constant { rows : Ok ( vec ! [ ] ) , typ , } , ) }
Take ownership of `self`, leaving an empty `MirRelationExpr::Constant` with the correct type.
Take ownership of ` self ` leaving an empty ` MirRelationExpr :: Constant ` with the correct type .
&mut self
&mut self