nushell/crates/nu-serde/README.md
Lily Mara 0a1cdc5107
Add the nu-serde crate (#3878)
* Add the nu-serde crate

nu-serde is a crate that can be used to turn a value implementing
`serde::Serialize` into a `nu-protocol::Value`. This has the potential to
significantly simplify plugin authorship.

This crate was the previously independent
[serde-nu](https://github.com/lily-mara/serde-nu) but the nushell maintainers
expressed an interest in having it added to the mainline nushell repository.

* fixup! Add the nu-serde crate
2021-07-31 22:03:13 -05:00

994 B

serde-nu

Convert any value implementing serde::Serialize into a nu_protocol::Value using nu_serde::to_value. Compare the below manual implemeentation and the one using nu_serde.

use nu_protocol::{Dictionary, Primitive, UntaggedValue, Value};
use nu_source::Tag;
use serde::Serialize;

#[derive(Serialize)]
struct MyStruct {
    index: usize,
    name: String,
}

fn manual(s: MyStruct, tag: Tag) -> Value {
    let mut dict = Dictionary::default();
    dict.insert(
        "index".into(),
        Value {
            value: UntaggedValue::Primitive(Primitive::Int(s.index as i64)),
            tag: tag.clone(),
        },
    );
    dict.insert(
        "name".into(),
        Value {
            value: UntaggedValue::Primitive(Primitive::String(s.name)),
            tag: tag.clone(),
        },
    );

    Value {
        value: UntaggedValue::Row(dict),
        tag,
    }
}

fn auto(s: &MyStruct, tag: Tag) -> Value {
    nu_serde::to_value(s, tag).unwrap()
}