https://issues.dlang.org/show_bug.cgi?id=20479

          Issue ID: 20479
           Summary: octal integer literals don't work with BetterC mode
           Product: D
           Version: D2
          Hardware: x86
                OS: Mac OS X
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: phobos
          Assignee: nobody@puremagic.com
          Reporter: bitworld@qq.com

import std.conv : octal;

extern(C) void main()
{
    enum a = octal!167; // bug
    enum b = octal!"167"; // ok
}

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