mailing-list for TeXmacs Users

[Henri Lesourd <address@hidden>]

address@hidden wrote:

> Hi TeXmacs users,
> I have been using Latex for serveral years and I are now looking for a more 
> userfriendly option for writing documentation and TeXmacs seems to be a good 
> alternative.
>
> I want to modify the "postscript" macro in a way, to display a default image if a 
> "dead" link is given as argument. Can anyone here help me a little?
>
> I have tried making a copy of the macro but I can get it to work (see example below). 
>
>
> <assign|postscript-copy|postscript>
>
> <postscript-copy|./image.eps||||||>
>
>  
If you do a copy a of the macro and change nothing, the
behaviour will remain the same anyway.

First, you should have a function :
[[
<is-dead-link|link>
]]

, which sends you back "true" or "false" according to if the link is 
dead or not.

One can write such a function as a TeXmacs macro by
means of an external Scheme routine, namely :
[[
<assign|is-dead-link|<macro|link|<extern|is-dead-link?|<arg|link>>>
]]

along with :
[[
(tm-define (is-dead-link? link)
 (if <<testing if the link is dead>>
    "true"
    "false"))
]]

(it is mandatory that inside such Scheme routines, you use
the strings "true" and "false", if you want that the <if>
construct of the TeXmacs macrolanguage understands you
correctly).


And then you write :
[[
<assign|my-postscript|
 <macro|link|...|
    <if|<is-dead-link|link>|My own image here|<postscript|link|...>
 >>
]]

, and then possibly (if this works, I'm not sure it will do it),
write :
[[
<assign|postscript|my-postscript>
]]

, but in case it doesnt, it should not be a huge
problem if you plan to start writing a new documentation
from scratch, you should use <my-postscript> instead
of <postscript>.

[I just tried : it doesn't work, the names
of predefined functions like <postscript>
are hardwired].


Best, Henri