aopt_core/value/
initializer.rs

1use std::fmt::Debug;
2
3use crate::map::ErasedTy;
4use crate::Error;
5
6use super::AnyValue;
7
8#[cfg(feature = "sync")]
9mod __initializer {
10
11    use super::*;
12
13    pub trait InitializeValue<T: ErasedTy>: Send + Sync {
14        type Error: Into<Error>;
15
16        fn prepare_value(&mut self) -> Result<T, Self::Error>;
17    }
18
19    impl<Func, Err, T: ErasedTy> InitializeValue<T> for Func
20    where
21        Err: Into<Error>,
22        Func: FnMut() -> Result<T, Err> + Send + Sync,
23    {
24        type Error = Err;
25
26        fn prepare_value(&mut self) -> Result<T, Self::Error> {
27            (self)()
28        }
29    }
30
31    pub type InitHandler<T> = Box<dyn FnMut(&mut T) -> Result<(), Error> + Send + Sync>;
32}
33
34#[cfg(not(feature = "sync"))]
35mod __initializer {
36
37    use super::*;
38
39    pub trait InitializeValue<T: ErasedTy> {
40        type Error: Into<Error>;
41
42        fn prepare_value(&mut self) -> Result<T, Self::Error>;
43    }
44
45    impl<Func, Err, T: ErasedTy> InitializeValue<T> for Func
46    where
47        Err: Into<Error>,
48        Func: FnMut() -> Result<T, Err>,
49    {
50        type Error = Err;
51
52        fn prepare_value(&mut self) -> Result<T, Self::Error> {
53            (self)()
54        }
55    }
56
57    pub type InitHandler<T> = Box<dyn FnMut(&mut T) -> Result<(), Error>>;
58}
59
60pub use __initializer::InitHandler;
61pub use __initializer::InitializeValue;
62
63/// A type using for initialize the option value.
64pub struct ValInitializer(InitHandler<AnyValue>);
65
66impl Debug for ValInitializer {
67    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
68        f.debug_tuple("ValInitializer").field(&"{...}").finish()
69    }
70}
71
72impl ValInitializer {
73    pub fn new<U: ErasedTy>(mut init: impl InitializeValue<Vec<U>> + 'static) -> Self {
74        Self(Box::new(move |erased_val| {
75            erased_val.set(init.prepare_value().map_err(Into::into)?);
76            Ok(())
77        }))
78    }
79
80    pub fn new_value<U: Clone + ErasedTy>(val: U) -> Self {
81        Self(Box::new(move |erased_val| {
82            erased_val.set(vec![val.clone()]);
83            Ok(())
84        }))
85    }
86
87    pub fn new_values<U: Clone + ErasedTy>(vals: Vec<U>) -> Self {
88        Self(Box::new(move |erased_val| {
89            erased_val.set(vals.clone());
90            Ok(())
91        }))
92    }
93
94    /// Default value initializer, do nothing.
95    pub fn fallback() -> Self {
96        Self(Box::new(|_| Ok(())))
97    }
98
99    pub fn invoke(&mut self, arg: &mut AnyValue) -> Result<(), Error> {
100        (self.0)(arg)
101    }
102
103    /// Get the default value.
104    pub fn values<T: ErasedTy>(&mut self) -> Result<Option<Vec<T>>, Error> {
105        let mut any_value = AnyValue::new();
106        self.invoke(&mut any_value)?;
107        Ok(any_value.remove())
108    }
109}
110
111#[cfg(not(feature = "sync"))]
112impl<T: FnMut(&mut AnyValue) -> Result<(), Error> + 'static> From<T> for ValInitializer {
113    fn from(value: T) -> Self {
114        Self(Box::new(value))
115    }
116}
117
118#[cfg(feature = "sync")]
119impl<T: FnMut(&mut AnyValue) -> Result<(), Error> + Send + Sync + 'static> From<T>
120    for ValInitializer
121{
122    fn from(value: T) -> Self {
123        Self(Box::new(value))
124    }
125}
aopt_core/value/initializer.rs

aopt_core/value/
initializer.rs
