Andrew V. Teylu
106da4905f
In the 2024 edition of Rust, `serde`s macros for `serialize_with` can
lead to a temporary lifetime error such as:
```
error[E0716]: temporary value dropped while borrowed
--> my-binary/src/main.rs:6:10
|
6 | #[derive(MyDerive)]
| ^^^^^^^-
| | |
| | temporary value is freed at the end of this statement
| creates a temporary value which is freed while still in use
| borrow later used by call
| in this derive macro expansion
|
::: /private/tmp/life/my-project/my-macro/src/lib.rs:6:1
|
6 | pub fn my_derive(_input: TokenStream) -> TokenStream {
| ---------------------------------------------------- in this expansion of `#[derive(MyDerive)]`
|
= note: consider using a `let` binding to create a longer lived value
```
This is because the macro code takes a reference to struct inside of a
block, which then goes out of scope when `serde` passes it to a
function.
To resolve this, we move the reference to outside of the block, to
ensure that the lifetime extends into the function call.
Signed-off-by: Andrew V. Teylu <andrew.teylu@vector.com>
Serde 
Serde is a framework for serializing and deserializing Rust data structures efficiently and generically.
You may be looking for:
- An overview of Serde
- Data formats supported by Serde
- Setting up
#[derive(Serialize, Deserialize)] - Examples
- API documentation
- Release notes
Serde in action
Click to show Cargo.toml. Run this code in the playground.
[dependencies]
# The core APIs, including the Serialize and Deserialize traits. Always
# required when using Serde. The "derive" feature is only required when
# using #[derive(Serialize, Deserialize)] to make Serde work with structs
# and enums defined in your crate.
serde = { version = "1.0", features = ["derive"] }
# Each data format lives in its own crate; the sample code below uses JSON
# but you may be using a different one.
serde_json = "1.0"
use serde::{Deserialize, Serialize};
#[derive(Serialize, Deserialize, Debug)]
struct Point {
x: i32,
y: i32,
}
fn main() {
let point = Point { x: 1, y: 2 };
// Convert the Point to a JSON string.
let serialized = serde_json::to_string(&point).unwrap();
// Prints serialized = {"x":1,"y":2}
println!("serialized = {}", serialized);
// Convert the JSON string back to a Point.
let deserialized: Point = serde_json::from_str(&serialized).unwrap();
// Prints deserialized = Point { x: 1, y: 2 }
println!("deserialized = {:?}", deserialized);
}
Getting help
Serde is one of the most widely used Rust libraries so any place that Rustaceans congregate will be able to help you out. For chat, consider trying the #rust-questions or #rust-beginners channels of the unofficial community Discord (invite: https://discord.gg/rust-lang-community), the #rust-usage or #beginners channels of the official Rust Project Discord (invite: https://discord.gg/rust-lang), or the #general stream in Zulip. For asynchronous, consider the [rust] tag on StackOverflow, the /r/rust subreddit which has a pinned weekly easy questions post, or the Rust Discourse forum. It's acceptable to file a support issue in this repo but they tend not to get as many eyes as any of the above and may get closed without a response after some time.
License
Licensed under either of Apache License, Version 2.0 or MIT license at your option.Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in Serde by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.