foldl1 is a variant of foldl that has no starting value
argument, and thus must be applied to non-empty ByteStrings. An
exception will be thrown in the case of an empty ByteString.
foldl1 is a variant of foldl that has no starting value
argument, and thus must be applied to non-empty
ShortByteStrings. An exception will be thrown in the case of an
empty ShortByteString.