Implement FromParts for Option, Result (#2068) (4eccaada) · Commits · Public Repositories / Smithy Rust

rust-runtime/aws-smithy-http-server/src/request/mod.rs

+30 −0

Original line number	Diff line number	Diff line
		@@ -36,6 +36,14 @@
		//!
		//! See [Accessing Un-modelled data](https://github.com/awslabs/smithy-rs/blob/main/design/src/server/from_parts.md)
		//! a comprehensive overview.
		//!
		//! The following implementations exist:
		//! * Tuples up to size 8, extracting each component.
		//! * `Option<T>`: `Some(T)` if extracting `T` is successful, `None` otherwise.
		//! * `Result<T, T::Rejection>`: `Ok(T)` if extracting `T` is successful, `Err(T::Rejection)` otherwise.
		//!
		//! when `T: FromParts`.
		//!

		use std::{
		convert::Infallible,
		@@ -236,3 +244,25 @@ where
		)
		}
		}

		impl<P, T> FromParts<P> for Option<T>
		where
		T: FromParts<P>,
		{
		type Rejection = Infallible;

		fn from_parts(parts: &mut Parts) -> Result<Self, Self::Rejection> {
		Ok(T::from_parts(parts).ok())
		}
		}

		impl<P, T> FromParts<P> for Result<T, T::Rejection>
		where
		T: FromParts<P>,
		{
		type Rejection = Infallible;

		fn from_parts(parts: &mut Parts) -> Result<Self, Self::Rejection> {
		Ok(T::from_parts(parts))
		}
		}