Angle Units For Trig Functions

I see that the Fortran 2023 spec has added a bunch of parallel trig
functions that work in degrees.

I find this sort of thing unnecessary. It seems conventional to add
functions for converting between degrees and radians, but a simpler way is
to simply define a conversion factor for each angle unit. One conversion
factor is simpler than two functions for each angle unit.

So trig functions always work in radians. Supposing we have

    real, parameter :: DEG = PI / 180
    real, parameter :: CIRCLE = 2 * PI
    real, parameter :: RAD = 1

Then

    sin(x) -- sin of x in radians
    sin(x * DEG) -- x is in degrees
    atan2(y, x) -- arctangent is in radians
    atan2(y, x) / DEG -- arctangent is in degrees

and we can furthermore have equivalences like

    sin(90 * DEG) = sin(0.25 * CIRCLE) = sin(PI / 2)

(to within rounding error, of course)

and it is easy enough to add other units, e.g.

    real, parameter :: GRAD = PI / 200

Anybody remember those?