0 if
phrase contains no words or
if phrase is not found.
Word matches are made independent of case. Several whitespace characters between
words in either
phrase or the receiving string are treated as
a single blank for the comparison, but, otherwise, the words must match
exactly."now is the time"~caselessWordPos("the") --> 3
"now is the time"~caselessWordPos("The") --> 3
"now is the time"~caselessWordPos("IS THE") --> 2
"now is the time"~caselessWordPos("is the") --> 2
"now is the time"~caselessWordPos("is time ") --> 0
"To be or not to be"~caselessWordPos("BE") --> 2
"To be or not to be"~caselessWordPos("BE",3) --> 6