neon/macro_internal/
mod.rs

1//! Internals needed by macros. These have to be exported for the macros to work
2
3use std::marker::PhantomData;
4
5pub use linkme;
6
7use crate::{
8    context::{Context, Cx, ModuleContext},
9    handle::Handle,
10    result::{JsResult, NeonResult},
11    types::{extract::TryIntoJs, JsValue},
12};
13
14#[cfg(feature = "serde")]
15use crate::types::extract::Json;
16
17#[cfg(all(feature = "napi-6", feature = "futures"))]
18pub use self::futures::*;
19
20#[cfg(all(feature = "napi-6", feature = "futures"))]
21mod futures;
22
23type Export<'cx> = (&'static str, Handle<'cx, JsValue>);
24
25#[linkme::distributed_slice]
26pub static EXPORTS: [for<'cx> fn(&mut ModuleContext<'cx>) -> NeonResult<Export<'cx>>];
27
28#[linkme::distributed_slice]
29pub static MAIN: [for<'cx> fn(ModuleContext<'cx>) -> NeonResult<()>];
30
31// Wrapper for the value type and return type tags
32pub struct NeonMarker<Tag, Return>(PhantomData<Tag>, PhantomData<Return>);
33
34// Markers to determine the type of a value
35#[cfg(feature = "serde")]
36pub struct NeonJsonTag;
37pub struct NeonValueTag;
38pub struct NeonResultTag;
39
40pub trait ToNeonMarker {
41    type Return;
42
43    fn to_neon_marker<Tag>(&self) -> NeonMarker<Tag, Self::Return>;
44}
45
46// Specialized implementation for `Result`
47impl<T, E> ToNeonMarker for Result<T, E> {
48    type Return = NeonResultTag;
49
50    fn to_neon_marker<Tag>(&self) -> NeonMarker<Tag, Self::Return> {
51        NeonMarker(PhantomData, PhantomData)
52    }
53}
54
55// Default implementation that takes lower precedence due to autoref
56impl<T> ToNeonMarker for &T {
57    type Return = NeonValueTag;
58
59    fn to_neon_marker<Tag>(&self) -> NeonMarker<Tag, Self::Return> {
60        NeonMarker(PhantomData, PhantomData)
61    }
62}
63
64impl<Return> NeonMarker<NeonValueTag, Return> {
65    pub fn neon_into_js<'cx, T>(self, cx: &mut Cx<'cx>, v: T) -> JsResult<'cx, JsValue>
66    where
67        T: TryIntoJs<'cx>,
68    {
69        v.try_into_js(cx).map(|v| v.upcast())
70    }
71}
72
73#[cfg(feature = "serde")]
74impl NeonMarker<NeonJsonTag, NeonValueTag> {
75    pub fn neon_into_js<'cx, T>(self, cx: &mut Cx<'cx>, v: T) -> JsResult<'cx, JsValue>
76    where
77        Json<T>: TryIntoJs<'cx>,
78    {
79        Json(v).try_into_js(cx).map(|v| v.upcast())
80    }
81}
82
83#[cfg(feature = "serde")]
84impl NeonMarker<NeonJsonTag, NeonResultTag> {
85    pub fn neon_into_js<'cx, T, E>(
86        self,
87        cx: &mut Cx<'cx>,
88        res: Result<T, E>,
89    ) -> JsResult<'cx, JsValue>
90    where
91        Result<Json<T>, E>: TryIntoJs<'cx>,
92    {
93        res.map(Json).try_into_js(cx).map(|v| v.upcast())
94    }
95}
96
97impl<Tag> NeonMarker<Tag, NeonValueTag> {
98    pub fn into_neon_result<T>(self, _cx: &mut Cx, v: T) -> NeonResult<T> {
99        Ok(v)
100    }
101}
102
103impl<Tag> NeonMarker<Tag, NeonResultTag> {
104    pub fn into_neon_result<'cx, T, E>(self, cx: &mut Cx<'cx>, res: Result<T, E>) -> NeonResult<T>
105    where
106        E: TryIntoJs<'cx>,
107    {
108        match res {
109            Ok(v) => Ok(v),
110            Err(err) => err.try_into_js(cx).and_then(|err| cx.throw(err)),
111        }
112    }
113}
neon/macro_internal/mod.rs

neon/macro_internal/
mod.rs
