Subject: bug#16731: 24.3.50; Latin small letter sharp s is not considered lower-case

From: Eli Zaretskii <[email-masked]>
Date: Thu, 13 Feb 2014 19:39:04 +0200

> From: Stefan Monnier <[email-masked]>
> Cc: [email-masked],  [email-masked]
> Date: Thu, 13 Feb 2014 12:10:49 -0500
> 
> >  /* True if C is upper case.  */
> > -INLINE bool uppercasep (int c) { return downcase (c) != c; }
> > +INLINE bool uppercasep (int c)
> > +{
> > +  Lisp_Object val;
> > +
> > +  if (downcase (c) != c)
> > +    return true;
> > +
> > +  if (NILP (Vunicode_category_table))
> > +    return false;
> > +
> > +  val = CHAR_TABLE_REF (Vunicode_category_table, c);
> > +  return INTEGERP (val) && XINT (val) == UNICODE_CATEGORY_Lu;
> > +}
>  
> Doesn't sound too bad.  But it does beg the question: why check
> (downcase (c) != c) at all, then?

Because it's faster, and for most characters will do the job.