Re: [ConTeXt] Re: pictures for numbers

[Hans Hagen <pragma@wxs.nl>]

At 04:06 PM 11/16/2001 +0100, Andres Loeh wrote:
> > Date: Fri, 16 Nov 2001 12:53:14 +0100
> > From: Hans Hagen <pragma@wxs.nl>
> > Subject: [ConTeXt] Re: pictures for numbers
>
>Hello again,
>
>thanks for your help so far. I tried to construct a solution out of
>Taco's and your remarks, and I got that far:
>
>%--BEGIN
>\useexternalfigure [sleutelI] [sleutelsI_new] [height=3ex]
>\useexternalfigure [sleutelV] [sleutelsV_new] [height=3ex]
>\useexternalfigure [sleutelX] [sleutelsX_new] [height=3ex]
>
>\def\Sleutels#1%
>   {\hbox{\expandafter\DoSleutels\romannumeral #1\relax}\relax}
>
>\def\DoSleutels#1%
>   {\if #1\relax
>      \let\next\relax
>    \else
>      \if #1i%
>        \externalfigure[sleutelI]
>      \else
>        \if #1v%
>          \externalfigure[sleutelV]
>        \else
>          \if #1x%
>            \externalfigure[sleutelX]
>          \else
>            \relax
>          \fi
>        \fi
>      \fi
>      \let\next\DoSleutels
>    \fi
>    \next}
>

>The generation of the pictures works perfectly as
>a standalone function. However, I want them to appear
>as chapter numbers. If I uncomment either the line marked
>%(1)% or the lines marked %(2)%, I get errors:
>
>(1):

As said, the #1 is not really a number but a whole bunch of info, liek font 
switches; try \showargument{#1} in your macro and you will see what i mean.

This is why you need the alternative that i send you. That one uses the raw 
number. If you want an uppercase rommannumeral, use

\def\MyNiceNumber#1%
   {\edef\TheRomanNumber{\Romannumerals\currentheadnumber}%
    \expandafter\handletokens\TheRomanNumber\with\MyRomanPicture}

\def\MyRomanPicture#1%
   {\hbox{\externalfigure[RomanDigit#1][widyh=1cm]}}

\setuphead[chapter][numbercommand=\MyNiceNumber]

\dorecurse{25}{\chapter{It Works}}

For this to work you need the following macro (which i made for patrick 
some weeks ago, in core-con, but that one generates a \relax:

\def\doRomannumerals#1#2\relax % spaces after ifcase prevent \relax
   {\ifnum#1#2<10
      \ifcase0#1#2 \or I\or II\or III\or IV\or V\or VI\or VII\or VIII\or IX\fi
    \else\ifnum#1#2<100
      \ifcase0#1   \or X\or XX\or XXX\or XL\or L\or LX\or LXX\or LXXX\or XC\fi
      \doRomannumerals#2\relax
    \else\ifnum#1#2<1000
      \ifcase0#1   \or C\or CC\or CCC\or CD\or D\or DC\or DCC\or DCCC\or CM\fi
      \doRomannumerals#2\relax
    \else\ifnum#1#2<4000
      \ifcase0#1   \or M\or MM\or MMM\fi
      \doRomannumerals#2\relax
    \else
      \uppercase\expandafter{\romannumeral#1#2}%
    \fi\fi\fi\fi}
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                                   Hans Hagen | PRAGMA ADE | pragma@wxs.nl
                       Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
  tel: +31 (0)38 477 53 69 | fax: +31 (0)38 477 53 74 | www.pragma-ade.com
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