https://issues.dlang.org/show_bug.cgi?id=21243

          Issue ID: 21243
           Summary: Allow lambdas to return auto ref
           Product: D
           Version: D2
          Hardware: x86_64
                OS: Linux
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: snarwin+bugzilla@gmail.com

Nested functions (to which lambdas are lowered) already support this, so
lambdas should too.

This will make it possible to, for example, enclose an arbitrary expression in a @trusted lambda without needing to check first whether the expression evaluates to an lvalue or an rvalue.

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