https://issues.dlang.org/show_bug.cgi?id=19018

          Issue ID: 19018
           Summary: Lexer allows invalid integer literals, like `0x`
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: trivial
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: kubo39@gmail.com

---
void main()
{
    assert(0b == 0); // can compile and run.
    assert(0B == 0);
    assert(0x == 0);
    assert(0x == 0);
    assert(0X == 0);
    assert(0x_ == 0);
    assert(0X_ == 0);
}

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