Crate for macro-free variadic tuple metaprogramming.

Rationale

As of writing this crate, Rust does not support variadic generics and does not allow to reason about tuples in general.

Most importantly, Rust does not allow one to generically implement a trait for all tuples whose elements implement it.

This crate attempts to fill the gap by providing a way to recursively define traits for tuples.

Tuple lists

Tuple (A, B, C, D) can be unambiguously mapped into recursive tuple (A, (B, (C, (D, ())))).

On each level it consists of a pair (Head, Tail), where Head is tuple element and Tail is a remainder of the list. For last element Tail is an empty list.

Unlike regular flat tuples, such recursive tuples can be effectively reasoned about in Rust.

This crate calls such structures "variadics" and provides a set of traits and macros allowing one to conveniently work with them.

Acknowledgements

This crate is based on tuple_list by VFLashM

MIT License

Copyright (c) 2020 Valerii Lashmanov

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