[texhax] Plain TeX: shorter `rightarrow' needed

[Rodolfo Medina]

On 8 February 2009 Rodolfo Medina wrote:

>>  > In order to denote an oriented $\Gamma$ line, I need to put a small
>>  > rightarrow over the $\Gamma$ symbol, such that the plain TeX
>>  > $\rightarrow$ is too long.
>>  >
>>  > Is there a way to get that, and how?


Uwe Lück <uwe.lueck at web.de> writes:

>>\vec{\Gamma}


At 21:05 08.02.09, Reinhard Kotucha wrote:

> "Missing $ inserted", otherwise I don't like that the arrow is italic while 
> Gamma is not. $\mathit{\vec{\Gamma}}$ and 
> $\mathop{\Gamma}^{\scriptscriptstyle\to}$ are bad as well. Placing 
> something on top of a capital letter is problematic in general. Note that 
> in (classical) Greek, diacritical marks are not set on top of capital 
> letters, but on their left (learnt this from Claudio Beccari, cf. my 
> http://de.wikipedia.org/wiki/Räter), or already that limits of sum or 
> integral symbols are set on their right in inline mode. What is the 
> convention in this field?


$\vbox{\ialign{#\crcr$\scriptscriptstyle\to$\crcr\noalign
                           {\kern.5pt\nointerlineskip}%
                                $\hfil\displaystyle{\Gamma}\hfil$\crcr}}$

(see definition of \overerightarrow in the TeXbook) looks very nice.

Rodolfo