# Functions
CloneSliceOrEmpty returns the copy of strs or empty strings slice if strs is a nil slice.
ContainsFold reports whether s contains, ignoring letter case, substr.
FilterOut returns a copy of strs with all strings for which f returned true removed.
SplitTrimmed slices str into all substrings separated by sep and returns a slice of the trimmed substrings between those separators with empty strings skipped.
WriteToBuilder is a convenient wrapper for strings.(*Builder).WriteString that deals with multiple strings and ignores errors, since they are guaranteed to be nil.