remove the call .iter()

[FuGangqiang]

No description provided.

[rust-highfive]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @brson (or someone else) soon.

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[alexcrichton]

r? @steveklabnik

Note that this may not be 100% idiomatic as this is iterating over the Vec<T> by value (e.g. it's calling .into_iter). Often times you may need to write for x in &vec for example.

[steveklabnik]

Yes, this should be &vec, r=me wiht that change

[Manishearth]

@bors: rollup r=steveklabnik

[bors]

@bors r=Manishearth 69bfb6f