clack_common/events/spaces/
id.rs

1use crate::events::EventSpace;
2use crate::events::spaces::core::CoreEventSpace;
3use clap_sys::events::CLAP_CORE_EVENT_SPACE_ID;
4use std::marker::PhantomData;
5
6/// An event space identifier, optionally tied to its [`EventSpace`] type `S`.
7///
8/// If `S` is the unit type `()`, then this means this identifier is not tied to any particular
9/// event space (i.e. it is type-erased).
10#[derive(Copy, Clone, Ord, PartialOrd, Eq, PartialEq)]
11pub struct EventSpaceId<S = ()> {
12    id: u16,
13    _space: PhantomData<S>,
14}
15
16impl<S> EventSpaceId<S> {
17    /// The raw numeric value that represents an invalid event space identifier.
18    pub const INVALID_ID: u16 = u16::MAX;
19
20    /// Returns raw numeric value of this identifier.
21    ///
22    /// The returned value cannot be equal to [`Self::INVALID_ID`].
23    #[inline]
24    pub const fn id(&self) -> u16 {
25        self.id
26    }
27
28    /// Returns the raw numeric value of the given identifier, or [`Self::INVALID_ID`] if the
29    /// `None` is passed.
30    #[inline]
31    pub const fn optional_id(this: &Option<Self>) -> u16 {
32        match this {
33            Some(i) => i.id,
34            None => u16::MAX,
35        }
36    }
37
38    /// Gets an event space ID from a numerical value, without performing any checks.
39    ///
40    /// # Safety
41    ///
42    /// The caller *must* ensure the event type is properly associated to the event space `S`.
43    /// The caller must also ensure the ID is not equal to [`Self::INVALID_ID`].
44    #[inline]
45    pub const unsafe fn new_unchecked(id: u16) -> Self {
46        Self {
47            id,
48            _space: PhantomData,
49        }
50    }
51}
52
53impl<'a, S: EventSpace<'a>> From<EventSpaceId<S>> for EventSpaceId<()> {
54    #[inline]
55    fn from(id: EventSpaceId<S>) -> Self {
56        Self {
57            id: id.id,
58            _space: PhantomData,
59        }
60    }
61}
62
63impl EventSpaceId<CoreEventSpace<'_>> {
64    /// Returns the identifier for the [`CoreEventSpace`].
65    ///
66    /// It is the only event space that has a constant, specific ID designated by the CLAP
67    /// specification, and which can be retrieved without using an event registry.
68    #[inline]
69    pub const fn core() -> Self {
70        Self {
71            id: CLAP_CORE_EVENT_SPACE_ID,
72            _space: PhantomData,
73        }
74    }
75}
76
77impl EventSpaceId<()> {
78    /// Creates a new, type-erased [`EventSpaceId`] from its raw numeric value.
79    ///
80    /// This returns `None` if the passed value is equal to [`Self::INVALID_ID`].
81    #[inline]
82    pub const fn new(id: u16) -> Option<Self> {
83        if id == u16::MAX {
84            None
85        } else {
86            Some(Self {
87                id,
88                _space: PhantomData,
89            })
90        }
91    }
92
93    /// Turns this unassociated event space ID into one associated with the given event space.
94    ///
95    /// # Safety
96    ///
97    /// The caller *must* ensure the event type is properly associated to the event space `S`.
98    #[inline]
99    pub const unsafe fn into_unchecked<S>(self) -> EventSpaceId<S> {
100        EventSpaceId::new_unchecked(self.id)
101    }
102}
clack_common/events/spaces/id.rs

clack_common/events/spaces/
id.rs
