xpatch 0.4.2

High-performance delta compression library with automatic algorithm selection
Documentation 
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// xpatch - High-performance delta compression library
// Copyright (c) 2025 Oliver Seifert
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published
// by the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <https://www.gnu.org/licenses/>.
//
// Commercial License Option:
// For commercial use in proprietary software, a commercial license is
// available. Contact xpatch-commercial@alias.oseifert.ch for details.

use xpatch::delta;

fn main() {
    let v1 = b"Hello";
    let v2 = b"Hello, World!";
    let v3 = b"Hello"; // Same as v1!

    println!("=== Naive Approach ===");
    // Always compare with immediate predecessor
    let delta_v1_to_v2 = delta::encode(0, v1, v2, false);
    println!("v1 -> v2 delta size: {} bytes", delta_v1_to_v2.len());

    let delta_v2_to_v3 = delta::encode(0, v2, v3, false);
    println!("v2 -> v3 delta size: {} bytes", delta_v2_to_v3.len());

    let naive_total = delta_v1_to_v2.len() + delta_v2_to_v3.len();
    println!("Naive total: {} bytes\n", naive_total);

    println!("=== Optimized Approach ===");
    // Compare v3 with v1 instead - they're identical!
    let delta_v1_to_v3 = delta::encode(1, v1, v3, false);
    println!("v1 -> v3 delta size: {} bytes", delta_v1_to_v3.len());
    println!("Tag=1 indicates base version\n");

    // Verify decoding works
    let reconstructed = delta::decode(v1, &delta_v1_to_v3[..]).unwrap();
    assert_eq!(reconstructed, v3);

    let tag = delta::get_tag(&delta_v1_to_v3[..]).unwrap();
    println!("Tag extracted: {}", tag);
}