The slash "/" as used in the documentation

[Jon Ribbens]

On 2019-02-09, Terry Reedy <tjreedy at udel.edu> wrote:
> '/' is no uglier than, and directly analogous to, and as easy to produce 
> and comprehend, as '*'.  It was selected after considerable discussion 
> of how to indicate that certain parameters are, at least in CPython, 
> positional only.  The discussion of options included at least some of 
> those given above.  It is very unlikely to go away or be changed.

Ok, but what does it *mean*?

As an aside, how is 'math.sin' actually implemented? mathmodule.c
refers to the function 'math_sin' but that name is not defined
anywhere in the Python source code. I'm a bit mystified as to how
CPython manages to compile!