Add type annotation pattern

[tathanhdinh]

Simple change to handle #5

[lambda-fairy]

Looks good so far.

Can you please add an example to the documentation as well?

[lambda-fairy]

Also, the Travis build fails on Rust 1.7.0. Can you please investigate?

I'm happy to bump the minimum supported version, but I'd like to know the reason behind the error first.

Thanks!

[tathanhdinh]

@lfairy sorry for the delay, I've updated the PR.
I've looked into the problem of failed compilation with rustc-1.7.0, unfortunately I still don't know what exactly the reason is. Maybe it comes from a bug of rust's parser at this version, there was a similar issue: rust-lang/rust#18775 (comment)

[lambda-fairy]

Thanks for looking into it.

I played around with the build and found that Rust 1.11.0 works but 1.10.0 doesn't. I'm happy with bumping the version requirement to 1.11.0.

Maybe it comes from a bug of rust's parser at this version, there was a similar issue: rust-lang/rust#18775 (comment)

That issue probably isn't relevant because it was fixed in 2014 when 1.11.0 was released in 2016.

Looking at the release notes, rust-lang/rust#34436 feels more likely. I found that nightly-2016-06-24 fails but nightly-2016-07-02 passes, which is strong evidence for that PR being the fix.

Can you please bump the minimum version to 1.11.0 and add an example to the documentation? Once that's done then I'll be happy to merge.

[hcpl]

@tathanhdinh are you still working on this PR? I would like to get this merged because I have a PR idea that touches your code along with other parts of if_chain!.

[tathanhdinh]

@hcpl

@tathanhdinh are you still working on this PR? I would like to get this merged because I have a PR idea that touches your code along with other parts of if_chain!.

Sorry, I forgot it. I will push the changed PR today.

[lambda-fairy]

Sorry about the delay! Looks good to me.