[Texmacs-dev] Re: [TeXmacs] macros, passing paramaters to with, and using includes

[Henri Lesourd]

Corey Sweeney wrote:

> I tried this:
>
> <assign|include-with-intro|<\macro|filename|intro>
>   <\with|intro-text|intro>
>     <include|/home/corey/sql-queries.tm <http://queries.tm>>
>   </with>
> </macro>>
>
> However, the parameter "intro" in <with|intro-text|intro|... refuses 
> to become a paramater from the macro (i.e. brown and italicized), and 
> becomes the literal text "intro".  Usually it happens automatically 
> when I hit tab.  Is there a way to force this to happen?
>
> I did try this first:
> <assign|include-with-intro|<\macro|filename|intro-text>
>   <include|/home/corey/sql-queries.tm <http://queries.tm>>
> </macro>>
>
> But then the included file believed that intro-text was not defined at 
> all.
I tried to do what you want ; I discovered that in any case, for some
obscure reason, the use of <include|...> inside a macro just doesn't
work :
[[
  <macro|inc0|<macro|x|<include|<arg|x>>>
]]

Thus the solution to this problem is to use Scheme for loading the
file. After having a look in build-glue-basic.scm, one can see that
there is a Scheme primitive that can perform loading a .tm file,
namely (tree-load-inclusion). Thus we write :
[[
  <macro|inc0|<macro|x|<extern|tree-load-inclusion|<arg|x>>>
]]

but it doesn't work, because before being a parameter
of (tree-load-inclusion), the <arg|x> must be converted
to the string type. Thus we (would) write :
[[
  <macro|inc0|<macro|x|<extern|(lambda (x) (tree-load-inclusion 
(tree->string x)))|<arg|x>>>
]]

But this one *still* doesn't work, due to address@hidden problems of
symbol encoding (for the symbol ">" in "tree->string"...), because
we want to write the Scheme code directly inside the TeXmacs <extern>
markup (the clean alternative solution would be to write a Scheme
plugin where we could safely write our Scheme functions. But then
we would have to deal with the current bug in the recently implemented
lazy evaluation of Scheme plugins ; I'm afraid that discussing this
would lead us even farther in designing hacks...).

Thus we need to trick it ; the following way works :
[[
  <macro|inc0|<macro|x|<extern|(lambda (x) (tree-load-inclusion
    ((eval-string (string-append "tree-" (substring ">" 4 5) "stree"))
    x)))|<arg|x>>>
]]

[it works because the ">" symbol is encoded by TeXmacs
as "<gtr>", thus {{ (substring ">" 4 5) }} is in fact
(after encoding) {{ (substring "<gtr>" 4 5) }}, thus
it yields ">" ; then the surrounding (string-append ...)
builds the name "tree->stree", and (eval-strings) turns
this name into the corresponding lambda ; finally, this
lambda is applied to the parameter 'x' ...].


Hope it helps :=P


Best, Henri


P.S. : Look at the two attached files, they contain an
 implementation of <include-file|filename|comment> that
 works, along with the different intermediary steps to
 build it.

<TeXmacs|1.0.6>

<style|generic>

<\body>
  <value|intro-text>

  A

  \;

  \;

  \;

  Hello!

  \;

  \;

  \;

  B
</body>

<\initial>
  <\collection>
    <associate|language|english>
    <associate|page-bot|1in>
    <associate|page-even|1in>
    <associate|page-odd|1in>
    <associate|page-right|1in>
    <associate|page-top|1in>
    <associate|page-type|letter>
    <associate|par-width|6.5in>
    <associate|preamble|false>
  </collection>
</initial>

<TeXmacs|1.0.6>

<style|generic>

<\body>
  <hrule>

  Initial include text :

  <with|intro-text|12345|<include|hello.tm>>

  <hrule>

  Initial version of the inc0 macro (that doesn't work) :

  <assign|inc0|<\macro|x>
    <include|<arg|x>>
  </macro>>

  <\inc0>
    hello.tm
  </inc0>

  <hrule>

  2nd version of inc0 (that works) :

  <assign|inc0|<macro|x|<extern|(lambda (x) (tree-load-inclusion
  ((eval-string (string-append "tree-" (substring "\<gtr\>" 4 5) "stree"))
  x)))|<arg|x>>>>

  <inc0|hello.tm>

  <hrule>

  Finally, the macro that does what we want :

  
<assign|include-file|<macro|file|intro|<with|intro-text|<arg|intro>|<inc0|<arg|file>>>>>

  <include-file|hello.tm|This is my introductary text>

  <hrule>
</body>

<\initial>
  <\collection>
    <associate|page-type|letter>
    <associate|preamble|true>
  </collection>
</initial>