whole_str finds haystack with "whole needles" with any non character as boundaries
part_str finds haystacks that match any of the needles
both_str will find haystacks that contain both needles
whole_str(haystack, needle)part_str(haystack, needle)
both_str(haystack, needle)
object in which to look for the needle
vector of strings to look for - accepts regular expressions
Other string matching functions:
getElem,
recodeye(),
sort_substr()