https://issues.dlang.org/show_bug.cgi?id=20534

          Issue ID: 20534
           Summary: std.format: %r on boolean gives wrong result
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: normal
          Priority: P1
         Component: phobos
          Assignee: nobody@puremagic.com
          Reporter: bugzilla@d-ecke.de

The output of %r on booleans gives 4 bytes, not only one, because the bool is cast to an int before it is formatted. This is inconsistent with other uses of %r (which is yet undocumented).

void main()
{
    import std.format : format;

    assert(format("%r",false) == "\0"); // fails
}

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