https://issues.dlang.org/show_bug.cgi?id=21237

          Issue ID: 21237
           Summary: isLvalueAssignable and isRvalueAssignable should be
                    public
           Product: D
           Version: D2
          Hardware: x86_64
                OS: Linux
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: phobos
          Assignee: nobody@puremagic.com
          Reporter: snarwin+bugzilla@gmail.com

Some types, such as types with @disabled copy constructors and types with opAssign overloads that accept the rhs only by ref, satisfy one but not the other. It would be useful for generic code to be able to distinguish these types from types that do not allow assignment at all.

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