Karpal v0.1.0

First public release of the Karpal HKT library for Rust — a GAT-based higher-kinded type system for the Industrial Algebra ecosystem.

Crates

Crate	Description
`karpal-core`	HKT encoding, full functor hierarchy, algebraic structures, comonads, macros (`no_std`)
`karpal-profunctor`	Profunctor, Strong, Choice with FnP (`no_std`)
`karpal-optics`	Profunctor optics: Lens, ComposedLens, Prism
`karpal-arrow`	Category/Arrow hierarchy: 8 traits + FnA, KleisliF, CokleisliF (`no_std`)
`karpal-std`	Prelude re-exports for all crates

GAT-based HKT encoding — trait HKT { type Of<T>; } / trait HKT2 { type P<A, B>; }, zero dependencies, stable since Rust 1.65
Full functor hierarchy — Functor, Apply, Applicative, Chain, Monad, Alt, Plus, Alternative, Bifunctor, Contravariant, Foldable, Traversable, FunctorFilter, Selective, NaturalTransformation
Comonad family — Comonad, Extend, ComonadEnv, ComonadStore, ComonadTraced, Invariant
Profunctor optics — Lens and Prism via profunctor encoding with composition support
Arrow hierarchy — Semigroupoid, Category, Arrow, ArrowChoice, ArrowApply, ArrowLoop, ArrowZero, ArrowPlus
do_! / ado_! macros — monadic and applicative do-notation
287 tests including property-based law verification via proptest
no_std compatible core crates (karpal-core, karpal-profunctor, karpal-arrow)

[dependencies]
karpal-std = "0.1.0"

use karpal_std::prelude::*;

let doubled = OptionF::fmap(Some(21), |x| x * 2);
assert_eq!(doubled, Some(42));