──┬───────┬─ <Boolean constant primary> ───────────────────────────────►
  └─ NOT ─┘
►─┬──────────────────────────────────────────────────────┬─────────────┤
  │ ┌◄─────────────────────────────────────────────────┐ │
  └─┴─┬─ AND ─┬─┬───────┬─ <Boolean constant primary> ─┴─┘
      ├─ OR ──┤ └─ NOT ─┘
      ├─ EQV ─┤
      └─ IMP ─┘──┬─ <Boolean constant> ──────────────────────┬────────────────────────┤ ├─ <Boolean constant identifier> ───────────┤ ├─ <arithmetic constant comparison> ────────┤ ├─ <string constant comparison> ────────────┤ └─ ( ── <Boolean constant expression> ── ) ─┘
<arithmetic constant comparison>
──┬─ <real constant expression ─────┬─ <real relation> ────────────────► └─ <integer constant expression> ─┘ ►─┬─ <real constant expression ─────┬──────────────────────────────────┤ └─ <integer constant expression> ─┘
── <string constant expression> ─┬─ = ───┬─────────────────────────────►
                                 ├─ EQL ─┤
                                 └─ NEQ ─┘
►─ <string constant expression> ───────────────────────────────────────┤Explanation
Refer to Boolean Expressions for explanations of the various kinds of Boolean expressions.

