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

wasm_wave/wasm/
ty.rs
