[COMMIT] Be better about key sequence syntax, po-mode.el

[Aidan Kehoe]

 Ar an triú lá de mí Méan Fómhair, scríobh Mats Lidell: 

 > >>>>> Norbert Koch <viteno at xemacs.org> writes:
 > 
 > Norbert> if I read the smoketest results correctly, this code does not compile
 > Norbert> (21.5 MULE output).
 > 
 > Yes and just evaulating this
 > 
 >  (define-key po-mode-map [(control c) (control #)]
 >     'po-edit-comment-and-ediff)
 > 
 > Give "Invalid read syntax". Should it be
 > 
 >  (define-key po-mode-map [(control c) (control ?#)]
 >     'po-edit-comment-and-ediff)

The canonical way of representing a key is as a symbol, so (control \#).
Your syntax is fine too.

 > Related: I guess there is some place in the manual where one can read
 > about such beasts as the #-char. It has some special maeaning for a
 > non lisper like me trying to learn, is there a pointer to some docs
 > here?

See the expression prefix syntax class in the Lispref, 

(Info-goto-node "(lispref.info)Syntax Class Table")

Basically, because # starts the read syntax for structures, quoted
functions, and compiled functions, it needs to be quoted to be treated as a
symbol constituent.

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