add post_async example usage

[baoyachi]

• add post_async example
• format code use command with cargo fmt

[codecov]

Codecov Report

Merging #273 (9a86688) into master (876cc03) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #273   +/-   ##
=======================================
  Coverage   72.96%   72.96%           
=======================================
  Files          51       51           
  Lines        2715     2715           
=======================================
  Hits         1981     1981           
  Misses        734      734           

Impacted Files	Coverage Δ
src/lib.rs	77.77% <ø> (ø)

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[sagebind]

format code use command with cargo fmt

I'd rather avoid using rustfmt for now as I haven't up until now; sometimes rustfmt makes some silly choices by default that I think makes it harder to read. I could make a rustfmt.toml file to correct those, I just haven't yet.

In addition, I think this complicates this PR when it could be a simpler diff. Formatting changes always have bigger diffs that can make it hard to spot changes when mixed with non-formatting changes.

[baoyachi]

format code use command with cargo fmt

I'd rather avoid using rustfmt for now as I haven't up until now; sometimes rustfmt makes some silly choices by default that I think makes it harder to read. I could make a rustfmt.toml file to correct those, I just haven't yet.

In addition, I think this complicates this PR when it could be a simpler diff. Formatting changes always have bigger diffs that can make it hard to spot changes when mixed with non-formatting changes.

How to unify the code style of multi-person development and avoid merge conflicts？

And cargo fmt support custom config:https://github.com/rust-lang/rustfmt/blob/master/Configurations.md

[sagebind]

I get the sentiment and to some extent I agree. I think using something like rustfmt is generally a good idea, but I disagree with the some of the default styling rules (and this isn't really the right forum to debate the specifics). And the way it works right now, almost all options are ignored unless you use the nightly Rust toolchain and nightly rustfmt.

In practice this has rarely been an issue, so I haven't bothered to address it specifically.

And cargo fmt support custom config:https://github.com/rust-lang/rustfmt/blob/master/Configurations.md

Indeed, but 99% of those options result in something like

Warning: can't set `imports_layout = "HorizontalVertical"`, unstable features are only available in nightly channel.

Because most of the useful options are nightly-only, and potential contributors are unlikely to switch to the nightly channel just to run cargo fmt.

[sagebind]

Seems good to me now, but could you please revert the unrelated formatting changes? I like to keep the diffs clean so it is easier to spot what a merged commit does in the future. Thanks.

[baoyachi]

It's has been roolback cargo fmt code

[sagebind]

Thanks!