Method narrower

cranelift/codegen/meta/src/cdsl/typevar.rs:263–265

Make a new [TypeVar] that includes all types narrower than self.

(&self)

    /// Make a new [TypeVar] that includes all types narrower than self.
    pub fn narrower(&self) -> TypeVar {
        self.derived(DerivedFunc::Narrower)
    }

    /// Make a new [TypeVar] that includes all types wider than self.
    pub fn wider(&self) -> TypeVar {