C= BASIC, 6502 Bytecode (then someone showed me what an assembler was), 6502 Assembly, PASCAL, FORTRAN, C, PERL, JAVA, C++, Pro-C, Objective C, Ruby, C#, and probably another dozen or more scripting and other languages I have used to accomplish what needed to get done over the years.... Don’t think I’ll ever stop learning new languages, as the need arises.
The more I know, the more options I have. I run into folks all the time who have let their skills rust, even though I mostly code only as a hobby these days, most of my day to day stuff isn’t in the code itself, my pay grade is such that I provide the direction to the coders. Love to code, dream in code, but the pay for a straight coder is below my pay grade anymore.
A person may be a great foxpro coder, but when the company finally decides its had enough of that, and they have no other skill, you are the first ones out the door.
Since you mention the 6502, or the 6510 in the same family that were used in the old Commodore VIC-20 and 64 computers...
Ever program in COMAL? I did a couple small CompSci grad school projects using COMAL way back in the day on my C64 :).