wasm_wave/wasm/
ty.rs

1use std::{borrow::Cow, fmt::Debug};
2
3/// The kind of a [`WasmType`]. These correspond to the value types defined by the
4/// [Component Model design](https://github.com/WebAssembly/component-model/blob/673d5c43c3cc0f4aeb8996a5c0931af623f16808/design/mvp/WIT.md).
5#[derive(Clone, Copy, Debug, PartialEq, Eq)]
6#[allow(missing_docs)]
7#[non_exhaustive]
8pub enum WasmTypeKind {
9    Bool,
10    S8,
11    S16,
12    S32,
13    S64,
14    U8,
15    U16,
16    U32,
17    U64,
18    F32,
19    F64,
20    Char,
21    String,
22    List,
23    FixedSizeList,
24    Record,
25    Tuple,
26    Variant,
27    Enum,
28    Option,
29    Result,
30    Flags,
31    #[doc(hidden)]
32    Unsupported,
33}
34
35impl std::fmt::Display for WasmTypeKind {
36    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
37        f.write_str(match self {
38            WasmTypeKind::Bool => "bool",
39            WasmTypeKind::S8 => "s8",
40            WasmTypeKind::S16 => "s16",
41            WasmTypeKind::S32 => "s32",
42            WasmTypeKind::S64 => "s64",
43            WasmTypeKind::U8 => "u8",
44            WasmTypeKind::U16 => "u16",
45            WasmTypeKind::U32 => "u32",
46            WasmTypeKind::U64 => "u64",
47            WasmTypeKind::F32 => "f32",
48            WasmTypeKind::F64 => "f64",
49            WasmTypeKind::Char => "char",
50            WasmTypeKind::String => "string",
51            WasmTypeKind::List => "list",
52            WasmTypeKind::FixedSizeList => "list<_,N>",
53            WasmTypeKind::Record => "record",
54            WasmTypeKind::Tuple => "tuple",
55            WasmTypeKind::Variant => "variant",
56            WasmTypeKind::Enum => "enum",
57            WasmTypeKind::Option => "option",
58            WasmTypeKind::Result => "result",
59            WasmTypeKind::Flags => "flags",
60            WasmTypeKind::Unsupported => "<<UNSUPPORTED>>",
61        })
62    }
63}
64
65/// The WasmType trait may be implemented to represent types to be
66/// (de)serialized with WAVE, notably [`value::Type`](crate::value::Type).
67/// The `wasmtime` crate provides an impl for `wasmtime::component::Type`.
68///
69/// The `Self`-returning methods should be called only for corresponding
70/// [`WasmTypeKind`]s.
71pub trait WasmType: Clone + Sized {
72    /// Returns the [`WasmTypeKind`] of this type.
73    fn kind(&self) -> WasmTypeKind;
74
75    /// Returns the list element type or `None` if `self` is not a list type.
76    /// # Panics
77    /// Panics if the type is not implemented (the trait default).
78    fn list_element_type(&self) -> Option<Self> {
79        unimplemented!()
80    }
81    /// Returns an iterator of the record's field names and Types. The
82    /// iterator will be empty iff `self` is not a record type.
83    /// # Panics
84    /// Panics if the type is not implemented (the trait default).
85    fn record_fields(&self) -> Box<dyn Iterator<Item = (Cow<'_, str>, Self)> + '_> {
86        unimplemented!()
87    }
88    /// Returns an iterator of the tuple's field Types. The iterator will be
89    /// empty iff `self` is not a tuple type.
90    /// # Panics
91    /// Panics if the type is not implemented (the trait default).
92    fn tuple_element_types(&self) -> Box<dyn Iterator<Item = Self> + '_> {
93        unimplemented!()
94    }
95    /// Returns an iterator of the variant's case names and optional payload
96    /// Types. The iterator will be empty iff `self` is not a tuple type.
97    /// # Panics
98    /// Panics if the type is not implemented (the trait default).
99    fn variant_cases(&self) -> Box<dyn Iterator<Item = (Cow<'_, str>, Option<Self>)> + '_> {
100        unimplemented!()
101    }
102    /// Returns an iterator of the enum's case names. The iterator will be
103    /// empty iff `self` is not an enum type.
104    /// # Panics
105    /// Panics if the type is not implemented (the trait default).
106    fn enum_cases(&self) -> Box<dyn Iterator<Item = Cow<'_, str>> + '_> {
107        unimplemented!()
108    }
109    /// Returns the option's "some" type or `None` if `self` is not an option type.
110    /// # Panics
111    /// Panics if the type is not implemented (the trait default).
112    fn option_some_type(&self) -> Option<Self> {
113        unimplemented!()
114    }
115    /// Returns the result's optional "ok" and "err" Types or `None` if `self`
116    /// is not a result type.
117    /// # Panics
118    /// Panics if the type is not implemented (the trait default).
119    fn result_types(&self) -> Option<(Option<Self>, Option<Self>)> {
120        unimplemented!()
121    }
122    /// Returns an iterator of the flags' names. The iterator will be empty iff
123    /// `self` is not a flags type.
124    /// # Panics
125    /// Panics if the type is not implemented (the trait default).
126    fn flags_names(&self) -> Box<dyn Iterator<Item = Cow<'_, str>> + '_> {
127        unimplemented!()
128    }
129}
130
131macro_rules! maybe_unwrap_type {
132    ($ty:expr, $case:path) => {
133        match $ty {
134            $case(v) => Some(v),
135            _ => None,
136        }
137    };
138}
139pub(crate) use maybe_unwrap_type;
wasm_wave/wasm/ty.rs

wasm_wave/wasm/
ty.rs
