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/*******************************************************************************
*
* Copyright (c) 2025 - 2026.
* Haixing Hu, Qubit Co. Ltd.
*
* All rights reserved.
*
******************************************************************************/
//! Defines the `BoxConsumerOnce` public type.
use *;
// ============================================================================
// 2. BoxConsumerOnce - Single Ownership Implementation
// ============================================================================
/// BoxConsumerOnce struct
///
/// One-time consumer implementation based on `Box<dyn FnOnce(&T)>` for single ownership scenarios.
/// This is the simplest consumer type for truly one-time use.
///
/// # Features
///
/// - **Single Ownership**: Not cloneable, transfers ownership on use
/// - **Zero Overhead**: No reference counting or lock overhead
/// - **One-time Use**: Consumes self on first call
/// - **Builder Pattern**: Method chaining naturally consumes `self`
///
/// # Use Cases
///
/// Choose `BoxConsumerOnce` when:
/// - Consumer is truly used only once
/// - Building pipelines where ownership flows naturally
/// - Consumer captures values that should be consumed
/// - Performance critical and cannot accept shared overhead
///
/// # Performance
///
/// `BoxConsumerOnce` has the best performance:
/// - No reference counting overhead
/// - No lock acquisition or runtime borrow checking
/// - Direct function call through vtable
/// - Minimal memory footprint (single pointer)
///
/// # Examples
///
/// ```rust
/// use qubit_function::{ConsumerOnce, BoxConsumerOnce};
///
/// let consumer = BoxConsumerOnce::new(|x: &i32| {
/// println!("Value: {}", x);
/// });
/// consumer.accept(&5);
/// ```
///
/// # Author
///
/// Haixing Hu
// All methods require T: 'static because Box<dyn FnOnce(&T)> requires it
// Use macro to generate Debug and Display implementations
impl_consumer_debug_display!;
// ============================================================================
// 3. Implement ConsumerOnce trait for closures
// ============================================================================
// Implement ConsumerOnce for all FnOnce(&T) using macro
impl_closure_once_trait!;