A compact representation of a
Word8 vector.
It has a lower memory overhead than a
ByteString and does not
contribute to heap fragmentation. It can be converted to or from a
ByteString (at the cost of copying the string data). It
supports very few other operations.
It is suitable for use as an internal representation for code that
needs to keep many short strings in memory, but it
should not
be used as an interchange type. That is, it should not generally be
used in public APIs. The
ByteString type is usually more
suitable for use in interfaces; it is more flexible and it supports a
wide range of operations.