Le 04/04/2016 18:54, Frank Mittelbach a écrit :

> guess this is a case of \protected being harmful

>

> Am 04.04.2016 um 18:16 schrieb Julien RIVAUD (_FrnchFrgg_):

>

>> \NewDocumentEnvironment{foo}{m}{%

>>      \begin{tabular}{#1}%

>> }{%

>>      \end{tabular}%

>> }

>>

>> \begin{document}

>>

>> \fbox{

>>      \begin{foo}{ccc}

>>          \hline

>>          Test & a & b \\

>>          \hline

>>      \end{foo}

>> }

>>

>> \fbox{

>>      \begin{tabular}{ccc}

>>          \hline

>>          Test & a & b \\

>>          \hline

>>      \end{tabular}

>> }

>>

>> \end{document}

>>

>> The first and second \fbox-es should produce the same output, but don't:

>> the foo environment starts a second line at closing time, before the

>> control is passed to the author-supplied closing code.

>

> actually that's not equiv, equiv would be something like defining "baz"

>

> \newenvironment{baz}[1]{%

>      \begin{tabular}{#1}%

> }{%

>      \end{tabular}%

> }



Sure, but even if \newenvironment had the bug, I would have considered 

it a problem in xparse.



>

> but yes, same difference

>

> reason is the following difference in processing:

>

> \show\endfoo

> \show\endbaz

>

>  > \endfoo=\protected macro:

> ->\environment foo end aux .

> l.10 \show\endfoo

>

> ?

>  > \endbaz=\long macro:

> ->\end {tabular}.

> l.17 \show\endbaz

>

> the  \protected hides the \crcr inside \endtabular.



And in fact it hides any \crcr we could put in our closing code... I 

thought that it had to do with protection (this mail is a spin-off from 

a P.S. in the other thread), because I had to unprotect some of my 

commands in my table stuff.



BTW, I wrote a package that parse CSS-like syntax to define properties 

of table cells, like real padding or min-width/height/depth (it also 

fixes the vertical alignment problem by taking the *real* height of the 

first row or the *real* depth of the last row into account, not just the 

strut box). It uses mdwtab as a base. For now it computes each cell 

#row-#col values, but doesn't support :nth-child() selectors (or any 

other selector than "td") so it is unfinished. Quite useful as a 

replacement for extrarowheight and/or vgap to get better table output 

(and I just found that it also affects amsmath's |cases|, so the parent 

selector needs to be handled soon).



I really need to learn to write proper .dtx files, and submit my stuff 

on CTAN.



Cheers,



Julien