[CLN-list] Types in cl_R

[Bruno Haible]

Isidro Cachadiña Gutiérrez wrote:
> If you
> are working with real number, you don't expect  complex numbers arriving
> elsewhere

That's a problem with your mathematical education, not a problem with CLN.

> I prefer an error warning if something like sqrt(-1) happen.

You get a compilation error if you write

     cl_R x, y, z;
     z = expt(x, y);

This makes you aware to check your formulas. You do that, then insert the
cast

     cl_R x, y, z;
     z = As(cl_R)(expt(x, y));

then CLN checks that the result is indeed a real number. What more do you
want?

The signature sqrt : cl_R -> cl_R is a convenience function which omits
the possibility of a compilation error. Maybe this is a disadvantage.

Bruno