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qubit_function/transformers/transformer/
rc_conditional_transformer.rs

1/*******************************************************************************
2 *
3 *    Copyright (c) 2025 - 2026.
4 *    Haixing Hu, Qubit Co. Ltd.
5 *
6 *    All rights reserved.
7 *
8 ******************************************************************************/
9//! Defines the `RcConditionalTransformer` public type.
10
11#![allow(unused_imports)]
12
13use super::*;
14
15// ============================================================================
16// RcConditionalTransformer - Rc-based Conditional Transformer
17// ============================================================================
18
19/// RcConditionalTransformer struct
20///
21/// A single-threaded conditional transformer that only executes when a
22/// predicate is satisfied. Uses `RcTransformer` and `RcPredicate` for shared
23/// ownership within a single thread.
24///
25/// This type is typically created by calling `RcTransformer::when()` and is
26/// designed to work with the `or_else()` method to create if-then-else logic.
27///
28/// # Features
29///
30/// - **Shared Ownership**: Cloneable via `Rc`, multiple owners allowed
31/// - **Single-Threaded**: Not thread-safe, cannot be sent across threads
32/// - **Conditional Execution**: Only transforms when predicate returns `true`
33/// - **No Lock Overhead**: More efficient than `ArcConditionalTransformer`
34///
35/// # Examples
36///
37/// ```rust
38/// use qubit_function::{Transformer, RcTransformer};
39///
40/// let double = RcTransformer::new(|x: i32| x * 2);
41/// let identity = RcTransformer::<i32, i32>::identity();
42/// let conditional = double.when(|x: &i32| *x > 0).or_else(identity);
43///
44/// let conditional_clone = conditional.clone();
45///
46/// assert_eq!(conditional.apply(5), 10);
47/// assert_eq!(conditional_clone.apply(-5), -5);
48/// ```
49///
50/// # Author
51///
52/// Haixing Hu
53pub struct RcConditionalTransformer<T, R> {
54    pub(super) transformer: RcTransformer<T, R>,
55    pub(super) predicate: RcPredicate<T>,
56}
57
58// Implement RcConditionalTransformer
59impl_shared_conditional_transformer!(
60    RcConditionalTransformer<T, R>,
61    RcTransformer,
62    Transformer,
63    into_rc,
64    'static
65);
66
67// Use macro to generate Debug and Display implementations
68impl_conditional_transformer_debug_display!(RcConditionalTransformer<T, R>);
69
70// Implement Clone for RcConditionalTransformer
71impl_conditional_transformer_clone!(RcConditionalTransformer<T, R>);