From: Kenneth Whistler (
Date: Wed Jan 26 2000 - 17:13:48 EST

Murray clarified:

> U+2118 isn't a capital; it's the Weierstrass p (pls see your handy Unicode
> 3.0 Standard :-),

For those who don't have this online, the name list entry for U+2118 in
Unicode 3.0 reads as follows:

        = Weierstrass elliptic function
        * actually this has the form of a lowercase calligraphic p, despite its name

and the clarifying text in Chapter 12, Symbols, p. 296, reads:

"Despite its name, U+2118 SCRIPT CAPITAL P is neither script nor capital --
it is uniquely the Weierstrass elliptic function derived from a calligraphic
lowercase p."

This is one of the small class of "things that aren't what they seem"
in Unicode.

Remember that Unicode names are merely fixed, unchanging labels for the
abstract character encoded. Since standardizers, being human, are fallible,
sometimes those labels got assigned inappropriately, and the glitches have
had to be ironed out one at a time as they are discovered. But knowing this,
be careful not to presume that character identity and properties
can always be derived from the name alone.


> so U+0070 would be more appropriate. But I think it would
> also be a mistake to consider any mapping to p. The Weierstrass p is its own
> symbol, unique in the world of symbols. To map it to another symbol loses
> its meaning. Such a mapping would be as bad as mapping alpha to the letter
> a, something done by default, sigh, by the Win32 WideCharToMultiByte()
> routine if you specify code page 1252.
> Murray
> > -----Original Message-----
> > From: John Cowan []
> > Sent: Wednesday, January 26, 2000 11:58 AM
> > To: Unicode List
> > Subject: U+2118 SCRIPT CAPITAL P
> >
> > Why doesn't U+2118 SCRIPT CAPITAL P have a compatibility decomposition?
> > <font> 0050 would be the obvious value, the same as for U+2119
> >

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