I wrote the foundation routines and then discovered that Richard Russell, BBC BASIC for Windows, had come up with a very similar idea at almost the same time; we have shared our thoughts, but have slightly different end results.
Long string variables have to be created by the equivalent of LET and they work by reference. The library replicates all the BASIC string keywords as PROCs or FNs and will deal with any combination of normal string variables and expressions and long strings.
Strings has been updated because some of the routine names were the same as in the Longs library. All routines are now prefixed by 's'. There are a few minor bug fixes.
A StrongHelp manual is included in the download.