Trait Tap4Ref 

pub trait Tap4Ref {
    // Provided methods
    fn tap4_with<'x, X: ?Sized + 'x, R, A1, A2, A3, A4>(
        &'x self,
        proj: impl FnOnce(&'x Self) -> &'x X,
        f: impl FnOnce(&'x X, A1, A2, A3, A4) -> R,
    ) -> impl FnOnce(A1, A2, A3, A4) -> &'x Self { ... }
    fn tap4_with_mut<'x, X: ?Sized + 'x, M, F, A1, A2, A3, A4>(
        &'x mut self,
        proj: impl FnOnce(&mut Self) -> &mut X,
        f: F,
    ) -> impl FnOnce(A1, A2, A3, A4) -> &'x mut Self
       where F: Tap4Fn<X, A1, A2, A3, A4, M> { ... }
}

Tap-style helpers for calling (first, A1..A4) -> R for side effects.

The tap4_with* methods call f with a (possibly projected) borrow of self, discard R, and return self to enable chaining.

Provided Methods

fn tap4_with<'x, X: ?Sized + 'x, R, A1, A2, A3, A4>( &'x self, proj: impl FnOnce(&'x Self) -> &'x X, f: impl FnOnce(&'x X, A1, A2, A3, A4) -> R, ) -> impl FnOnce(A1, A2, A3, A4) -> &'x Self

Calls f(proj(&self), a1..a4) (immutable view), discards the return value, and returns &self.

fn tap4_with_mut<'x, X: ?Sized + 'x, M, F, A1, A2, A3, A4>( &'x mut self, proj: impl FnOnce(&mut Self) -> &mut X, f: F, ) -> impl FnOnce(A1, A2, A3, A4) -> &'x mut Self

where F: Tap4Fn<X, A1, A2, A3, A4, M>,

Calls f(proj(&mut self), a1..a4) (mutable view), discards the return value, and returns &mut self.

This method accepts both immutable Fn(&X) and mutable Fn(&mut X) functions.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors

impl<T: ?Sized> Tap4Ref for T