| It uses mathematical notation for ranges and sets to define the intervals with : |
| n1 equals to field = n1, |
{n1,n2,...} equals to field = n1 OR field = n2 OR ... |
| [n1,n2] equals to n1 <= field <= n2, |
[n1,n2[ equals to n1 <= field < n2 |
| ]n1,n2[ equals to n1 < field < n2, |
]n1,n2] equals to n1 < field <= n2 |
| [n1 equals to n1 <= field, |
]n1 equals to n1 < field |
| n2] equals to field <= n2, |
n2[ equals to field < n2. |
