Nested eperl tags

[Petr Andreyev <nospam@thanx>]

Hi Denis,

i'm glad that WML will be developed further. What are the  directions of the
future WML development, except for fixing existing problems?

===

We have discovered a couple of bugs in embedded eperl tags construction.
Here is an example:


========= code ====================================
#use wml::std::tags
<define-tag extern endtag=required>
<perl>
{
    my $body;
    <perl:print> BEFORE BODY\n </perl:print>
    <perl:assign $body>%body</perl:assign>
    <perl:print> YET BEFORE BODY\n </perl:print>
    <perl:print: $body />
}
</perl>
</define-tag>
<define-tag intern whitespace=delete>
<perl>
{
    <perl:print> BODY %0 </perl:print>
}
</perl>
</define-tag>

<extern>
   BEGIN BODY
   <intern 1 />
   MID MODY
   <intern 2 />
   END BODY
</extern>
===============================================

====== output with wml -p 1,2,3,8 ============
 BEFORE BODY
   BEGIN BODY
    BODY 1
   MID MODY
    YET BEFORE BODY
  BODY 2
   END BODY
==============================================

===== the same with our tags.wml====
 BEFORE BODY
  YET BEFORE BODY
   BEGIN BODY
    BODY 1
   MID MODY
    BODY 2
   END BODY
===============================

This demonstrates one bug. The another one is that there is two printing
modes: "double quoted" and 'single quoted'. But when when an inner printing
finishes and we are in an outer printing again, the double quoted mode is
always assumed.

I can propose a fix for both, the diff with the november version is attached.
It allows for using <perl tags inside other <perl tags as well, but I don't
know wheter this is very useful - probably for defining some tags working
inside <perl and outside.

Greetings
--
Petr

diff