arctic-map 0.1.0

Lock-free adaptive radix tree
Documentation 
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//! Weakly typed implementation of adaptive radix tree.
//!
//! The purpose of this module is to re-use as much code as possible between the
//! sequential ([`crate::sequential::Map`]) and concurrent ([`crate::concurrent::Map`])
//! tree implementations, and between instantiations of these trees with different
//! value types.
//!
//! This module contains:
//! - Structural types ([`crate::raw::edge`], [`crate::raw::node`], [`crate::raw::key`])
//! - Traversal for point operations ([`crate::raw::cursor`])
//! - Iteration for scan operations ([`crate::raw::iter`])
//!
//! This module is "raw" with respect to:
//! - Safe memory reclamation ([`crate::concurrent::smr`])
//! - Mutable vs. immutable access
//! - Value types ([`crate::sequential::Value`], [`crate::concurrent::Value`])

pub(crate) mod cursor;
pub(crate) mod edge;
pub(crate) mod iter;
pub mod key;
pub(crate) mod map;
pub(crate) mod node;
pub(crate) mod set;
pub(crate) mod shard;

pub(crate) use cursor::Cursor;
pub(crate) use edge::Edge;
pub use key::Key;
pub(crate) use map::Map;
pub(crate) use set::Set;
pub(crate) use shard::Shard;

/// Structural modification operation.
#[derive(Copy, Clone, Debug, PartialEq, Eq)]
pub(crate) enum Smo {
    ReplaceNode,
    DeleteNode,
    CompressEdge,
}

impl Smo {
    #[inline]
    pub fn is_allocate(self) -> bool {
        matches!(self, Self::ReplaceNode)
    }
}

fn is_unique(keys: &[u8]) -> bool {
    let mut seen = [0u128; 2];
    for key in keys {
        let row = key / 128;
        let col = key % 128;
        let bit = 1 << col;
        if seen[row as usize] & bit > 0 {
            return false;
        }
        seen[row as usize] |= bit;
    }
    true
}