Trait Arity

pub trait Arity {
    // Required method
    fn arity() -> usize;
}

Trait for getting the arity of a value. You shouldn’t need to impl this yourself.

Required Methods

fn arity() -> usize

Gets the arity of the type.

Example

use tuple_arity::Arity;
 
assert_eq!(0, <()>::arity());
assert_eq!(1, <(u8,)>::arity());
assert_eq!(2, <(u8, u8)>::arity());
assert_eq!(3, <(u8, u8, u8)>::arity());
assert_eq!(4, <(u8, u8, u8, u8)>::arity());

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.

Implementations on Foreign Types

impl Arity for ()

fn arity() -> usize

impl<T1> Arity for (T1,)

fn arity() -> usize

impl<T1, T2> Arity for (T1, T2)

fn arity() -> usize

impl<T1, T2, T3> Arity for (T1, T2, T3)

fn arity() -> usize

impl<T1, T2, T3, T4> Arity for (T1, T2, T3, T4)

fn arity() -> usize

impl<T1, T2, T3, T4, T5> Arity for (T1, T2, T3, T4, T5)

fn arity() -> usize

impl<T1, T2, T3, T4, T5, T6> Arity for (T1, T2, T3, T4, T5, T6)

fn arity() -> usize

impl<T1, T2, T3, T4, T5, T6, T7> Arity for (T1, T2, T3, T4, T5, T6, T7)

fn arity() -> usize

impl<T1, T2, T3, T4, T5, T6, T7, T8> Arity for (T1, T2, T3, T4, T5, T6, T7, T8)

fn arity() -> usize

impl<T1, T2, T3, T4, T5, T6, T7, T8, T9> Arity for (T1, T2, T3, T4, T5, T6, T7, T8, T9)

fn arity() -> usize

impl<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10> Arity for (T1, T2, T3, T4, T5, T6, T7, T8, T9, T10)

fn arity() -> usize

impl<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11> Arity for (T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11)

fn arity() -> usize

impl<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12> Arity for (T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12)

fn arity() -> usize

Implementors