std_mel/ops/option/
mod.rs

1use melodium_core::*;
2use melodium_macro::{check, mel_function, mel_treatment};
3
4pub mod block;
5
6/// Unwrap option of return default value
7#[mel_function(
8    generic T ()
9)]
10pub fn unwrap_or(option: Option<T>, default: T) -> T {
11    option.unwrap_or(default)
12}
13
14/// Unwrap option stream
15///
16/// Unwrap every option in stream, ignoring values set to _none_.
17#[mel_treatment(
18    generic T ()
19    input option Stream<Option<T>>
20    output value Stream<T>
21)]
22pub async fn unwrap() {
23    while let Ok(values) = option
24        .recv_many()
25        .await
26        .map(|values| Into::<VecDeque<Value>>::into(values))
27    {
28        check!(
29            value
30                .send_many(TransmissionValue::Other(
31                    values
32                        .into_iter()
33                        .filter_map(|val| match val {
34                            Value::Option(Some(val)) => Some(*val),
35                            _ => None,
36                        })
37                        .collect()
38                ))
39                .await
40        )
41    }
42}
43
44/// Unwrap option stream with default value
45///
46/// Unwrap every option in stream, sending `default` value when option is _none_.
47#[mel_treatment(
48    generic T ()
49    input option Stream<Option<T>>
50    output value Stream<T>
51)]
52pub async fn unwrap_or(default: T) {
53    while let Ok(values) = option
54        .recv_many()
55        .await
56        .map(|values| Into::<VecDeque<Value>>::into(values))
57    {
58        check!(
59            value
60                .send_many(TransmissionValue::Other(
61                    values
62                        .into_iter()
63                        .filter_map(|val| match val {
64                            Value::Option(Some(val)) => Some(*val),
65                            Value::Option(None) => Some(default.clone()),
66                            _ => None,
67                        })
68                        .collect()
69                ))
70                .await
71        )
72    }
73}
74
75/// Unwrap option stream until _none_ is present
76///
77/// Unwrap every option in stream, and stop at the first _none_ value encountered.
78#[mel_treatment(
79    generic T ()
80    input option Stream<Option<T>>
81    output value Stream<T>
82)]
83pub async fn fuse() {
84    'main: while let Ok(values) = option
85        .recv_many()
86        .await
87        .map(|values| Into::<VecDeque<Value>>::into(values))
88    {
89        for val in values {
90            match val {
91                Value::Option(Some(val)) => check!('main, value.send_one(*val).await),
92                _ => break 'main,
93            }
94        }
95    }
96}
97
98/// Wrap a value in an option
99#[mel_function(
100    generic T ()
101)]
102pub fn wrap(value: T) -> Option<T> {
103    Some(value)
104}
105
106/// Wrap values in options
107///
108/// Takes a stream of values and turn them into filled options.
109#[mel_treatment(
110    generic T ()
111    input value Stream<T>
112    output option Stream<Option<T>>
113)]
114pub async fn wrap() {
115    while let Ok(values) = value
116        .recv_many()
117        .await
118        .map(|values| Into::<VecDeque<Value>>::into(values))
119    {
120        check!(
121            option
122                .send_many(TransmissionValue::Other(
123                    values
124                        .into_iter()
125                        .map(|val| Value::Option(Some(Box::new(val))))
126                        .collect()
127                ))
128                .await
129        )
130    }
131}
std_mel/ops/option/mod.rs

std_mel/ops/option/
mod.rs
