Correct subtyping relations in pattern checking#20517

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bors merged 3 commits intorust-lang:masterfrom

nikomatsakis:safety-issue-19997

Jan 6, 2015

Commits on Jan 4, 2015

Correct the subtyping relations created by the pattern typechecking
nikomatsakis
committed
Miscellaneous reformatting and commenting.
nikomatsakis
committed
Cleanup type-checking of constants, but do not try to fix #20489.
nikomatsakis
committed