POS

Syntax:     POS(find str,source str[,n])

Defn:       A CI evaluator function that finds the nth occurrence
            of specified string in a source string, beginning either
            from the left (when n is positive) or the right (when n
            is negative).

Type:       Integer

Example:    pos('ab','cgabd')
Result:     3

Example:    pos('b','abcbe',2)
Result:     4

Example:    pos('b','abcbe',-1)
Result:     4