Struct sp_runtime_interface::pass_by::Inner
source · pub struct Inner<T: PassByInner<Inner = I>, I: RIType>(_);
Expand description
The implementation of the pass by inner type strategy. The type that uses this strategy will be passed between wasm and the host by using the wrapped inner type. So, this strategy is only usable by newtype structs.
Use this type as associated type for PassBy
to implement this strategy for a type. Besides
that the PassByInner
trait need to be implemented as well.
This type expects the type that wants to use this strategy as generic parameter T
and the
inner type as generic parameter I
.
PassByInner
is a derive macro to implement this strategy.
Example
struct Test([u8; 32]);
impl PassBy for Test {
type PassBy = Inner<Self, [u8; 32]>;
}
impl PassByInner for Test {
type Inner = [u8; 32];
fn into_inner(self) -> [u8; 32] {
self.0
}
fn inner(&self) -> &[u8; 32] {
&self.0
}
fn from_inner(inner: [u8; 32]) -> Self {
Self(inner)
}
}
Trait Implementations§
source§impl<T: PassByInner<Inner = I>, I> PassByImpl<T> for Inner<T, I>where
I: IntoFFIValue + FromFFIValue<SelfInstance = I> + RIType,
impl<T: PassByInner<Inner = I>, I> PassByImpl<T> for Inner<T, I>where I: IntoFFIValue + FromFFIValue<SelfInstance = I> + RIType,
source§fn into_ffi_value(
instance: T,
context: &mut dyn FunctionContext
) -> Result<Self::FFIType>
fn into_ffi_value( instance: T, context: &mut dyn FunctionContext ) -> Result<Self::FFIType>
Convert the given instance to the ffi value. Read more
source§fn from_ffi_value(
context: &mut dyn FunctionContext,
arg: Self::FFIType
) -> Result<T>
fn from_ffi_value( context: &mut dyn FunctionContext, arg: Self::FFIType ) -> Result<T>
Create
T
from the given ffi value. Read more