## Examples

-      "One Thousand Five Hundred" =~ "(T[^ ]+)"
         returns: Thousand

       "One Thousand Five Hundred" =~ "T[^ ]+"
         returns: 8

       "One Thousand Five Hundred" : "T[^ ]+"
         returns: 0

       "8015551212" : "(...)"
         returns: 801

       "3075551212":"...(...)"
         returns: 555

       ! "One Thousand Five Hundred" =~ "T[^ ]+"
         returns: 0 (because it applies to the string, which is non-null,
                          which it turns to "0", and then looks for the pattern
                          in the "0", and doesn't find it)

       !( "One Thousand Five Hundred" : "T[^ ]+" )
         returns: 1  (because the string doesn't start with a word starting
                           with T, so the match evals to 0, and the ! operator
                           inverts it to 1 ).

       2 + 8 / 2
         returns 6. (because of operator precedence; the division is done first, then the addition).

       2+8/2
         returns 6. Spaces aren't necessary.

      (2+8)/2
         returns 5, of course.

      (3+8)/2
         returns 5.5 now.

      TRUNC((3+8)/2)
         returns 5.

      FLOOR(2.5)
         returns 2

      FLOOR(-2.5)
         returns -3

      CEIL(2.5)
         returns 3.

      CEIL(-2.5)
         returns -2.

      ROUND(2.5)
         returns 3.

      ROUND(3.5)
         returns 4.

      ROUND(-2.5)
         returns -3

      RINT(2.5)
         returns 2.

      RINT(3.5)
         returns 4.

      RINT(-2.5)
         returns -2.

      RINT(-3.5)
         returns -4.

      TRUNC(2.5)
         returns 2.

      TRUNC(3.5)
         returns 3.

      TRUNC(-3.5)
         returns -3.

Of course, all of the above examples use constants, but would work the same if any of the numeric or string constants were replaced with a variable reference ${CALLERID(num)}, for instance.