Extend examples to show more than just a single `task::block_on`

[brandonros]

Can somebody add an example of what this would look like:

const foo = async function () { return 1 }
const bar = async function () { return 1 }
const results = await Promise.all([foo(), bar()])

I think having just a single task::block_on in each example isn't very "real world"

[yoshuawuyts]

@brandonros the equivalent with async-std would be:

use async_std::task;

async fn foo() -> u8 {
    1
}

async fn bar() -> u8 {
    1
}

fn main() {
    task::block_on(async {
        let results = foo().join(bar()).await;
    })
}

Or with the "attributes" feature enabled in Cargo.toml, and using closures, we can shorten it somewhat:

#[async_std::main]
async fn main() {
    let foo = || async move { 1 };
    let bar = || async move { 1 };
    let results = foo().join(bar()).await);
}

This will improve in the future once we have language-level support for async closures. e.g. let foo = async || 1;

But you're right tho, we should consider adding a larger example to our docs. Even if it's a single extra call, it might be useful for people new to async rust to see what it's like. Thanks for raising this!

[omac777]

I totally agree there should be more examples surrounding the task::block_on.

For example how do we pass in arguments into this task block?
Everything I attempted to pass in i.e. &str, &Vec all give me compiler errors that the variables do not survive lifetime of variable at the close of the task block. I don't mind that, but I need to pass data into it in order to make these task blocks useful. Hard-coded strings are static and not useful as an example to use this stuff.

@omac777 Can you provide an example of code that gives this lifetime error?