# Sing
**S**td
**I**/o
**N**egotiator
**G**enerator
[](https://crates.io/crates/sing_rs)
[](https://www.gnu.org/licenses/agpl-3.0.html)
## What is sing?
This crate is meant to create interfaces between traits in Rust libraries and the command line.
It does this by providing two macros:
- `sing_add_trait`, which acts as an attribute to a trait implementation and gathers the method signatures that are used by `sing_loop!`.
- `sing_loop!`, which takes a trait object and serialization/deserialization functions as well as some optional parameters. It generates a loop parsing function calls coming from STDIN (or any other `BufRead` stream), evaluating them by calling the appropriate method on the object and returning them on STDOUT (or any other `Write` stream).
## Usage example
```rust
use serde::{Serialize, Deserialize};
use sing_rs::{sing_add_trait, sing_loop};
trait FruitTree {
fn shake(&self, shakes: u32) -> Vec<Fruit>;
}
#[derive(Debug, Serialize, Deserialize)]
struct Fruit {
fruit_type: String,
}
struct BananaTree;
#[sing_add_trait()]
impl FruitTree for BananaTree {
fn shake(&self, shakes: u32) -> Vec<Fruit>{
let mut out = vec!();
for _ in 0..shakes {
out.push(Fruit{fruit_type: String::from("Banana")});
}
out
}
}
fn main() {
let tree = BananaTree {};
sing_loop!(tree, [different, ron::to_string, ron::from_str],);
}
```
## Negotiator? Really?
Yes, it's somewhat far-fetched, but I really wanted to be able to sing and [clap](https://github.com/clap-rs/clap) in my rusty command-line projects.
## Why the name?
See above.