Adding `try_future` library as a dependency

Run this command in a terminal, in your project's directory:

cargo add try_future

To add it manually, edit your project's Cargo.toml file and add to the [dependencies] section:

try_future = "0.1.3"

The try_future library will be automatically available globally. Read the try_future library documentation.

Back to the crate overview.

Readme

`try_future`

This crate aims to provide a convenient short-hand for returning early from futures-based functions.

The general pattern it supports is where before a function performs an asynchronous task, it does some work that might result in an early termination, for example:

certain parsing or validation logic might fail, upon which the function should return immediately with an error
some local cache lookup or other optimization that might render the asynchronous task unnecessary, and where the function would want immediately return a value instead

Examples

Using `impl Future<_>`

#[macro_use] extern crate try_future;

fn make_request<C: Connect>(target: &str, client: &Client<C>) ->
    impl Future<Item=Response, Error=Error>
{
    let uri = try_future!(target.parse::<Uri>());

    client.get(uri).into()
}

Using `Box<Future<_>>`

#[macro_use] extern crate try_future;

fn make_request<C: Connect>(target: &str, client: &Client<C>) ->
    Box<Future<Item=Response, Error=Error>>
{
    let uri = try_future_box!(target.parse::<Uri>());

    Box::new(client.get(uri))
}

Adding try_future library as a dependency

Adding `try_future` library as a dependency