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pneumatic (1.1.0)

Published 2026-09-19 06:31:17 +00:00 by decduck

Installation

Setup this registry in the Cargo configuration file (for example ~/.cargo/config.toml):

[registries.forgejo]
index = "sparse+" # Sparse index
# index = "" # Git

[net]
git-fetch-with-cli = true

To install the package using Cargo, run the following command:

cargo add pneumatic@1.1.0 --registry forgejo

For more information on the Cargo registry, see the documentation.

About this package

pneumatic

pneumatic provides static delegation from an enum to the single-field tuple variants it wraps.

use std::future::Future;
use pneumatic::{pneumatic_trait, Pneumatic};

#[pneumatic_trait]
trait Operation {
    fn name(&self) -> String;
    fn run(&self) -> impl Future<Output = String>;
}

#[derive(Pneumatic)]
#[pneumatic(Operation)]
enum Operations {
    First(First),
    Second(Second),
}

The trait attribute records method signatures in a hidden callback macro. The enum derive consumes that method list and creates a match over every variant. Methods returning impl Future<Output = T> become async fn methods returning T; each variant call is awaited inside its match arm.

The enum must use one-field tuple variants, and delegated methods must have a receiver with identifier-pattern arguments. Generic methods are not currently supported. Rust does not allow derive macros on traits, so traits use the pneumatic_trait attribute.

When the trait and enum live in different modules or files, import the trait module with #[macro_use] so the generated method metadata macro is visible to the enum module:

#[macro_use]
mod traits;
mod enums;

Run the example test with:

cargo test

Dependencies

ID	Version
proc-macro2	^1
quote	^1
syn	^2
futures	^0.3

Details

Cargo

2026-09-19 06:31:17 +00:00

11

8.5 KiB

Assets (1)

pneumatic-1.1.0.crate 8.5 KiB

Versions (2) View all

1.1.0 2026-09-19

1.0.0 2026-09-19