You're right, Tom, it did, and it should. It's a bug.
Like Scarlett O'Hara, I'm going to think about it tomorrow.
I've been recoding math/uu to work with rational numbers throughout. This
is one of the traps I've put in, to catch any floats slipping though. Alas,
boxed arguments to uu have not been in my test suite, because they're going
to be an undocumented feature of uu, which I was planning to support for
string arguments only.
Are you aiming to make serious use of math/uu, or are you simply exploring
what it can do?
Either way it stands to reason you'd want to work with quantities to higher
precision than you get by having to turn all your values to strings.
Presently the ways to do this are:
1. use convert_uu_
This accepts units, not whole quantities, and returns the conversion
factor to SI base-units.
To convert one arbitrary units to another, you call convert twice, once for
each units, and take the quotient of the conversion factors.
convert_uu_ 'ft'
┌─┬─┬────────┐
│m│0│381r1250│
└─┴─┴────────┘
convert_uu_ 'g/mol'
┌──────┬─┬──────┐
│kg/mol│0│1r1000│
└──────┴─┴──────┘
convert_uu_ 'cal/g'
┌───────┬─┬────┐
│m^2/s^2│0│4184│
└───────┴─┴────┘
2. use the all-purpose keyhole interface: uuengine_uu_
At present undocumented – the only way to find out what it does is RTC.
(…but it's very easy code to read.)
3. treat uu as a class, and access attributes and methods via a numbered
locale. Study the code of math/cal/cal.ijs to see how to use it this way.
(Thus, find all instances of '__uun')
These days I'd strongly recommend against using math/uu via 3. A public
interface via itty-bitty calls and state-variables turns out to be a
monster to support.
Instead uuengine will be offered as the API for math/uu, because it
collects all the sensible ways to use math/uu into one keyhole interface
that comes with a single readable test script. Hey – and even a lab, when I
get time to write it.
If you want a survival-guide to calling uuengine, I can post one, or better
still, write a jwiki page.
Ian Clark
On Sun, 28 Apr 2019 at 05:33, Tom Arneson <[email protected]> wrote:
> I seem to remember that uu would accept boxed right argument (y) and
> return value;unit, but now this:
>
>
> uu '100 ft'
> 30.480 m
> uu 100;'ft'
> |assertion failure: uu_uu_
> | notFloat ratarg=.ralu scale_displace~rcoeft,rcoefu,rdispt,rdispu
>
>
> uu '100';'ft'
> |assertion failure: uu_uu_
> | notFloat ratarg=.ralu scale_displace~rcoeft,rcoefu,rdispt,rdispu
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