object_rainbow/
extra_option.rs1use crate::{extras::Extras, *};
2
3#[derive(Enum, Debug, Clone, PartialEq, ListHashes, Topological, Tagged)]
4#[rainbow(untagged)]
5pub enum ExtraOption<T, E = ()> {
6 Some(T),
7 None(Extras<E>),
8}
9
10impl<T, E> ExtraOption<T, E> {
11 pub fn as_ref(&self) -> Option<&T> {
12 match self {
13 Self::Some(value) => Some(value),
14 Self::None(_) => None,
15 }
16 }
17
18 fn new(extra: Extras<E>, value: Option<T>) -> Self {
19 match value {
20 Some(value) => Self::Some(value),
21 None => Self::None(extra),
22 }
23 }
24
25 pub fn from_tuple((extra, value): (Extras<E>, Option<T>)) -> Self {
26 Self::new(extra, value)
27 }
28
29 pub fn none(extra: E) -> Self {
30 Self::None(Extras(extra))
31 }
32}
33
34pub trait ExtraNoneOutput<E>: Sized {
35 fn extra_some_output(&self, output: &mut impl Output);
36 fn extra_none_output(extra: &E, output: &mut impl Output);
37 fn extra_option_output(option: &ExtraOption<Self, E>, output: &mut impl Output) {
38 match option {
39 ExtraOption::Some(value) => value.extra_some_output(output),
40 ExtraOption::None(extra) => Self::extra_none_output(extra, output),
41 }
42 }
43}
44
45impl<T: OptionOutput, E> ExtraNoneOutput<E> for T {
46 fn extra_some_output(&self, output: &mut impl Output) {
47 T::to_option_output(Some(self), output);
48 }
49
50 fn extra_none_output(_: &E, output: &mut impl Output) {
51 T::to_option_output(None, output);
52 }
53
54 fn extra_option_output(option: &ExtraOption<Self, E>, output: &mut impl Output) {
55 T::to_option_output(option.as_ref(), output);
56 }
57}
58
59impl<T: ExtraNoneOutput<E>, E> ToOutput for ExtraOption<T, E> {
60 fn to_output(&self, output: &mut impl Output) {
61 T::extra_option_output(self, output);
62 }
63}
64
65impl<T: OptionOutput + InlineOutput, E> InlineOutput for ExtraOption<T, E> {}
66
67impl<T: OptionParse<I>, I: PointInput> Parse<I> for ExtraOption<T, I::Extra> {
68 fn parse(input: I) -> crate::Result<Self> {
69 input.parse().map(Self::from_tuple)
70 }
71}
72
73impl<T: OptionParseInline<I>, I: PointInput> ParseInline<I> for ExtraOption<T, I::Extra> {
74 fn parse_inline(input: &mut I) -> crate::Result<Self> {
75 input.parse_inline().map(Self::from_tuple)
76 }
77}
78
79impl<T: CanonicalExtra<Extra = E>, E: Clone> CanonicalExtra for ExtraOption<T, E> {
80 type Extra = T::Extra;
81
82 fn canonical_extra(&self) -> Self::Extra {
83 match self {
84 Self::Some(value) => value.canonical_extra(),
85 Self::None(extra) => extra.canonical_extra(),
86 }
87 }
88}