[Jprogramming] RFC: unicode

[Elijah Stone]

On Sun, 20 Mar 2022, Raul Miller wrote:

> Deprecation based on something which has not been implemented is bad 
> news.

What are you getting at?  That I did not include a deprecation plan in my 
proposal?  I would like to first establish what the ideal semantics should 
_be_.  Getting there is secondary.


> It's my understanding that ucs-2 is a subset of utf-16.

More or less.  But j plays fast and loose with utf, and in particular 
could have ignored surrogates.


> Every primitive is in some sense "inconsistent" with other primitives, 
> because every primitive accomplishes something different.
>
> The ": primitive is about formatting text for display. That is going to 
> have to be different from an operation like addition.

Arguably, - is inconsistent, as x-y takes _x_ as primary data, and moves y 
units with respect to it.  More famously, % and | are not consistent with 
each other, as % takes its divisor on the right, and | takes its divisor 
on the left. I could argue that % and - should be flipped (and others 
_have_ argued thus).  But I don't, because there are also merits to the 
extant scheme.  To wit, % and - follow existing mathematical and 
programming notation (as does |; a|b can be used to denote that b is 
divisible by a), and they behave sensibly and usefully as monads.

But--two issues.

The first is that ": must still stand on its own merits; it is not enough 
to say that inconsistency is inevitable.  Why is this the best way to 
format text?  And is consistency between primitives _undesriable_?  Under 
my proposed semantics, ": would behave consistently with other primitives.

Second, and more important, is that the inconsistency is different in 
kind.  % and | agree that a 5 is a 5.  But whereas ": thinks that (8 
u:243) is a LATIN SMALL LETTER O WITH ACUTE, other primitives think that 
it is a LATIN CAPITAL LETTER A WITH TILDE followed by a SUPERSCRIPT THREE.


> Ah, that was my browser / email client messing up.

Just to avoid any ambiguity: the correct display of z is as a lowercase a, 
uppercase A overstruck with a tilde, superscript 3, lowercase b.


> I think a point has been lost here on why getting rid of u: would not 
> change anything about the initial example in this thread:

I think I addressed this; maybe I was not clear enough.  Removing u: alone 
is not sufficient to solve the problem; but it is necessary, and my 
proposal in its entirety remedies the problem.