All returns true if all of the strings in the slice satisfy the predicate f.

Any returns true if one of the strings in the slice satisfies the predicate f.

Filter returns a new slice containing all strings in the slice that satisfy the predicate f.

Include return true if the target string t is in slice.

Index Returns the first index of target string or -1 if no match found.

Map returns a new slice containing the result of applying f to each string.