Trait UnitTuple 

pub trait UnitTuple: TupleLen<Len = U0> { }

A marker trait for empty tuples (size 0).

This trait is implemented for the unit type () and can be used for type-level programming to identify empty tuples.

Examples

use tuplities_len::{UnitTuple, TupleLen};
use typenum::U0;

fn is_empty<T: UnitTuple>(_tuple: T) {
    // This function only accepts empty tuples
}

is_empty(()); // This works
// is_empty((1,)); // This would not compile

Part of the tuplities crate.

Dyn Compatibility

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementations on Foreign Types

impl UnitTuple for ()

Implementors