cleaned up trans/consts

[oli-obk]

turned some matches into if lets.

[rust-highfive]

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

If any changes to this PR are deemed necessary, please add them as extra commits. This ensures that the reviewer can see what has changed since they last reviewed the code. Due to the way GitHub handles out-of-date commits, this should also make it reasonably obvious what issues have or haven't been addressed. Large or tricky changes may require several passes of review and changes.

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[bors]

☔ The latest upstream changes (presumably #29929) made this pull request unmergeable. Please resolve the merge conflicts.

[oli-obk]

rebased

[bors]

☔ The latest upstream changes (presumably #25570) made this pull request unmergeable. Please resolve the merge conflicts.

[oli-obk]

rebased

[bors]

☔ The latest upstream changes (presumably #30084) made this pull request unmergeable. Please resolve the merge conflicts.

[oli-obk]

rebased and simplified this PR to only change some matches into if let. The other changes will be in their own PRs.

[pnkfelix]

@bors r+ b853115 rollup

[bors]

⌛ Testing commit b853115 with merge c98d5e7...

[bors]

💔 Test failed - auto-mac-64-opt

[oli-obk]

spurious git failure

[alexcrichton]

@bors: retry

On Fri, Dec 11, 2015 at 3:10 AM, Oliver Schneider notifications@github.com
wrote:

spurious git failure in travis

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Reply to this email directly or view it on GitHub
#30110 (comment).

[bors]

⌛ Testing commit b853115 with merge 97c4863...

[bors]

💔 Test failed - auto-mac-64-opt

[alexcrichton]

@bors: retry

On Fri, Dec 11, 2015 at 11:54 PM, bors notifications@github.com wrote:

[image: 💔] Test failed - auto-mac-64-opt
http://buildbot.rust-lang.org/builders/auto-mac-64-opt/builds/7365

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#30110 (comment).

[bors]

⌛ Testing commit b853115 with merge 45a73c8...

[bors]

☀️ Test successful - auto-linux-32-nopt-t, auto-linux-32-opt, auto-linux-64-debug-opt, auto-linux-64-nopt-t, auto-linux-64-opt, auto-linux-64-x-android-t, auto-linux-cross-opt, auto-linux-musl-64-opt, auto-mac-32-opt, auto-mac-64-nopt-t, auto-mac-64-opt, auto-win-gnu-32-nopt-t, auto-win-gnu-32-opt, auto-win-gnu-64-nopt-t, auto-win-gnu-64-opt, auto-win-msvc-32-opt, auto-win-msvc-64-opt