When I'm approaching a problem in C++ or python, there are many libraries that exist which do the heavy lifting of my code. I'm thinking about GNU GSL, BOOST, or FFTW for C++, and NumPy or SciPy for python. In many ways, the fact that these resources exist make coding in these respective languages worthwhile, as the libraries prevent you from having to rewrite all the low level things from scratch.
The IEEE standard libraries seem to cover only the very basics, such as data types (sort of akin to the C standard libs).
It seems like in VHDL, you can buy/find some "IP Cores" that will solve a problem, rather than using an open source library. In python, if I want to talk to a serial device, I just
import serial and I'm basically done. In VHDL I would either be stuck writing a serial protocol from scratch, or I would have to google around on the various repositories until I found someone who had produced something that sort of works. I would then be patching bits of code into my project, rather than just including something and calling that. In a similar way, if I want to perform an FFT, I can find examples of FFTs in VHDL via google, but there is not something simple like FFTW that I can find.
Are there any comprehensive open source libraries available that I can import into my projects? Why does everyone seem to roll their own code for so many of the same things?