https://issues.dlang.org/show_bug.cgi?id=22100

          Issue ID: 22100
           Summary: Support chained assignment of Nullable
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: phobos
          Assignee: nobody@puremagic.com
          Reporter: dlang-bugzilla@thecybershadow.net

This should work:

Nullable!int a, b, c;
a = b = c = 5;
a = b = c = nullable(5);

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