[Python-ideas] SI scale factors alone, without units or dimensional analysis

[Stephen J. Turnbull]

Ken Kundert writes:

 > The rule is you cannot give unit without a scale factor, and the
 > unity scale factor is _, so if you wanted to say 1 mol you would
 > use 1_mol. 1mol means one milli ol.  These look a little strange,
 > but that is because the use they unit scale factor, which is the
 > one that is currently not in heavy use.

One reason I like Python is that it has relatively few of these
irregularities and ambiguities (in comparison to other languages and
non-programming contexts with similar usage).  For me, that counts
against this proposal.

BTW, where is "_" used as the unit scale prefix?

 > I suggest that we do not support the h (=100), da (=10), d (=0.1),
 > or c (=0.01) scale factors.

I don't think it's reasonable to exclude those.  Around me, cm, dB,
and ha (centimeters, decibels, and hectares) are in common use.  What
happened to "support with a capital S"?

I don't speak for anybody but myself, but I think this proposal has
gotten less interesting/acceptable with each post.  I'm going wait and
see if the "units are types" approach goes anywhere.  I think it's
probably the only one that has wings, but that's because it requires
no change to the language.