Subteam report: lang 2015-06-02

Highlights

The following RFCs are entering final comment period:

PR #1131: Add an expect intrinsic.
PR #1052: Clarify cast rules, especially regarding fat pointers.
- Extended from last week.
PR #1122: Semantic versioning for the language.
PR #987: Modify RFC #803 (type ascription) to make type ascription expressions lvalues

Last week, we moved a number of RFCs into the final comment period:

PR #1052: Clarify cast rules, especially regarding fat pointers.
- No decision. FCP has been extended to give time for more discussion on some of the finer points.
PR #1096: remove static_assert.
- Accepted, tracking issue #24910.
PR #982: DST custom coercions.
- Accepted, tracking issue #18469. Note that much of this implementation has been done, but the design is not considered fully stabilized.
PR #591: Sizeof, alignof, offsetof, typeof
- Postponed as issue #1144 to allow room to explore a variant based on associated constants.
PR #948: Retire RFC 8 (intrinsics) without implementing it.
- Accepted.

I'd also like to highlight PR 25796, by @arielb1, which implemented defaults for associated types. Nice!

--- nmatsakis

PR #197: ManuallyDrop type gives precise control of dtors of inline data.
PR #243: Trait-based exception handling
PR #638: Specify unwinding
PR #697: Disallow omitting the ABI in extern declarations
PR #733: Amend macro future proofing RFC
PR #756: Allow closure expressions to expand to a & or &mut temporary
PR #865: Update RFC 195 to account for RFC 246.
PR #873: Allow macros in types
PR #890: RFC: Custom preludes
PR #948: Retire RFC 8 (intrinsics) without implementing it.
PR #953: overloaded assignment operations a += b
PR #982: DST custom coercions.
PR #987: Modify RFC #803 (type ascription) to make type ascription expressions lvalues
PR #1052: Clarify cast rules, especially regarding fat pointers.
PR #1062: Constants that depend on type parameters in generic code
PR #1096: remove static_assert
PR #1122: RFC: Semantic versioning for the language
PR #1129: IndexAssign: overloading the a[b] = c expression
PR #1131: Add an expect intrinsic
PR #1135: Implement raw fat pointer comparisons

Issue #25310: Passing a Fn to an fn now requires explicit lifetimes for the Fn and all references passed to it when invoked
Issue #25860: Implied bounds on nested references + variance = soundness hole