newRPL: Angles revisited

[Han]

(04-01-2016 05:33 PM)Helix Wrote:  

(04-01-2016 12:50 AM)Claudio L. Wrote:  For example, ∡12° 360 / is no longer an angle

Why?
For me, 10°+10°+10° = 3x10° = 30°, and 30°/3 = 10°.
I think that an angle multiplied or divided by a constant (a real number) should be an angle.

My guess would be ambiguity in interpreting the real number -- is it a constant multiplier, or did the user intentionally leave off the ° but still wanted to actually have degrees. In the former, you have what is essentially the same as your examples; in the latter, you would be looking at fractions of a circle (as one possible interpretation). With addition, there is only one reasonable meaning of something like 30° + 3. The only thing you can really add to angle (or perhaps temperature) is a change in angle (temp), so there is no ambiguity.