//! Gene trait definition.
//!
//! The [`GeneT`] trait is the smallest building block of a chromosome. Every
//! gene carries an integer ID (used for allele identity and duplicate
//! detection) and must be cloneable and thread-safe.
/// Trait that every gene type must implement.
///
/// A gene is a single element inside a chromosome's DNA. Implementations
/// must provide [`GeneT::set_id`]; the remaining methods have sensible
/// defaults.
///
/// # Required bounds
///
/// `Default + Clone + Sync + Send` — genes are created in bulk during
/// initialization and shared across threads by rayon.