This seems the same as "Unicode" and the technique is interesting.

A while back I had to use unicode to create a simple filled box in a 
tcl/tk window. It had a red foreground to look like an LED indicator. 
The 4 red boxes had a glyph representation ;
\u2588\u2588\u2588\u2588

It took quite a while to go through thousands of glyphs, just to find 
what used to be (IIRC) extended ASCII.

I would be interested in the actual programs doing this conversion. I 
think the tcl interpreter script uses the "\u" to flag the unicode 
example above.

Been a while. Surprised I found this old stuff.

Mike Miller wrote:
> It was bugging me that on Facebook, if I typed something like -20°F, the
> line might wrap between the minus and the 20. Then I read in Wikipedia
> that there is a minus sign, different from the hyphen:
>
> http://en.wikipedia.org/wiki/Plus_and_minus_signs#Minus_sign
>
> Copying/pasting that solved my problem, but that created the new problem
> that I want to be able to type the minus without having to go to
> Wikipedia to copy/paste it.
>
> That's when I found out that I can type any UTF character by first
> hitting ctrl-shift-u, then typing the number, then hitting space. The
> minus is #2212, so this does the trick:
>
> ctrl-shift-u
> 2212
> space
>
> Alternatively, I can hold down the ctrl-shift while typing the numbers,
> instead of releasing after the u, and then the UTF character appears
> when I release ctrl-shift and I don't have to hit the space.
>
> That doesn't work in every program, though. It worked in my browsers on
> Ubuntu, but I don't even know if it works outside of Ubuntu. I don't
> know how to use it in Emacs.
>
> There are UTF characters for °C (#2103) and °F (#2109):
>
> −40 ℃ = −40 ℉
>
> They don't look so great in some fonts, though.
>
> Anyway, I thought some of you would be interested in that trick. I
> hadn't heard of it before, but I could be the last one. ;-)
>
> Mike
>
>
>
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