Harbour is an xbase language. There is a large and very active community (see the FiveTech Forum as one of many.)
For those who have heard of Clipper and dBase III, Harbour is one of the more popular implementations of that language and is available on Linux, Windows and others. (There is a dotnet implementation, X#, that may be worth a look.)
@ajborla has already done extensive work on exercises and a test framework and there is enough material there to get the track going in a few weeks rather than months.
Itās a tricky situation but yes I think harbour is the best. I could name it āxbaseā but thereās never been a language or product of that name. Itās a generic term as below
XbaseāGeneric term for the dBASE family of database languages. Coined in response to threatened litigation over use of the copyrighted trademark ādBASEā.ā FOLDOC Free On-Line Dictionary Of Computing
xBase is the generic term for all programming languages that derive from the original dBase (Aston-Tate) programming language. There are indicators that there was a non-commercial predecessor. Wikipedia, the free encyclopedia
Thereās a harbour icon but no xbase one. Theyāre are quite a few groups producing xbase compilers. Harbour is the most well known of the open source compilers.
There is the possibility that someone wonāt be happy that Harbour was chosen. However, there is sufficient similarity on the core language that code written for Harbour can, with minimal adjustment, be made to work, for example, in X#.