nicematrix (16apr18)

git-svn-id: svn://tug.org/texlive/trunk@47545 c570f23f-e606-0410-a88d-b1316a301751

4 files changed, 470 insertions, 113 deletions

diff --git a/Master/texmf-dist/doc/latex/nicematrix/README.md b/Master/texmf-dist/doc/latex/nicematrix/README.md
index bf01c561311..30055711b03 100644
--- a/Master/texmf-dist/doc/latex/nicematrix/README.md
+++ b/Master/texmf-dist/doc/latex/nicematrix/README.md
@@ -4,5 +4,7 @@ This extension has been written by F. Pantigny (fpantigny@wanadoo.fr).
 
 This extension is entirely contained in a single file : nicematrix.sty
 
-The LaTeX package nicematrix gives an environment NiceMatrix which is similar to environment
-matrix but gives the possibility to draw ellipis dots between the cells of the matrix.
\ No newline at end of file
+The LaTeX package nicematrix provides new environments similar to the classical environments
+array and matrix but with some additional features. Among these features are the
+possibilities to fix the width of the columns and to draw continuous ellipsis dots between the cells
+of the array.
\ No newline at end of file
diff --git a/Master/texmf-dist/doc/latex/nicematrix/nicematrix.pdf b/Master/texmf-dist/doc/latex/nicematrix/nicematrix.pdf
index f3ec61447c7..4acb39a6d0c 100644
--- a/Master/texmf-dist/doc/latex/nicematrix/nicematrix.pdf
+++ b/Master/texmf-dist/doc/latex/nicematrix/nicematrix.pdf
diff --git a/Master/texmf-dist/source/latex/nicematrix/nicematrix.dtx b/Master/texmf-dist/source/latex/nicematrix/nicematrix.dtx
index c6f81ecfd46..5093c59642a 100644
--- a/Master/texmf-dist/source/latex/nicematrix/nicematrix.dtx
+++ b/Master/texmf-dist/source/latex/nicematrix/nicematrix.dtx
@@ -15,8 +15,8 @@
 %
 % \fi
 % \iffalse
-\def\myfileversion{1.3}
-\def\myfiledate{2018/03/31}
+\def\myfileversion{1.4}
+\def\myfiledate{2018/04/16}
 %
 %
 %<*batchfile>
@@ -70,8 +70,8 @@ version 2005/12/01 or later.
 %
 % \begin{abstract}
 % The LaTeX package \pkg{nicematrix} provides new environments similar to the classical environments |{array}| and
-% |{matrix}| but with some additional features. Among these features is the possibility to draw continuous ellipsis
-% dots between the cells of the array.
+% |{matrix}| but with some additional features. Among these features are the possibilities to fix the width of the
+% columns and to draw continuous ellipsis dots between the cells of the array.
 % \end{abstract}
 %
 % \vspace{1cm}
@@ -79,8 +79,8 @@ version 2005/12/01 or later.
 %
 %
 % This package can be used with |xelatex|, |lualatex|, |pdflatex| but also by the classical workflow
-% |latex|-|dvips|-|ps2pdf| (or Adobe Distiller). Two compilations may be necessary. This package requires the
-% packages \pkg{expl3}, \pkg{l3keys2e}, \pkg{xparse}, \pkg{array}, \pkg{mathtools} and \pkg{tikz}. 
+% |latex|-|dvips|-|ps2pdf| (or Adobe Distiller). Two or three compilations may be necessary. This package requires
+% the packages \pkg{expl3}, \pkg{l3keys2e}, \pkg{xparse}, \pkg{array}, \pkg{mathtools} and \pkg{tikz}.
 %
 % \medskip
 % The package \pkg{nicematrix} aims to draw beautiful matrices in a way almost transparent for the user.
@@ -247,7 +247,10 @@ version 2005/12/01 or later.
 %
 % \bigskip
 % There are also other means to change the size of the matrix. Someone might want to use the optional argument of
-% the command~|\\| for the vertical dimension and a command~|\hspace*| in a cell for the horizontal dimension.
+% the command~|\\| for the vertical dimension and a command~|\hspace*| in a cell for the horizontal
+% dimension.\footnote{Nevertheless, the best way to fix the width of a column is to use the environment
+% |{NiceArray}| with a column of type~|w| (or |W|).}
+% 
 % However, a command~|\hspace*| might interfer with the construction of the dotted lines. That's why the package
 % \pkg{nicematrix} provides a command~|\Hspace| which is a variant of |\hspace| transparent for the dotted lines of
 % \pkg{nicematrix}.\par\nobreak
@@ -362,6 +365,9 @@ version 2005/12/01 or later.
 % \medskip
 % The option |nullify-dots| smashes the instructions |\Ldots| (and the variants) vertically but also horizontally.
 %
+%
+% 
+% \vskip1cm
 % \section{How to use nicematrix for existing code}
 %
 % The package \pkg{nicematrix} provides an option called |transparent| for using existing code transparently in the
@@ -426,12 +432,13 @@ version 2005/12/01 or later.
 % \item The commands |\Cdots| and its variants are available in the environment |{NiceArray}|.
 % \item The environment |{NiceArray}| accepts (between brackets) the options |t|, |c| and |b| as the classical
 % |{array}| but also the following options defined by \pkg{nicematrix}: |renew-dots|, |nullify-dots|,
-% |exterior-arraycolsep| and |parallelize-diags| (these last two options are technical options described further).
-% \item For technical reasons, in the preamble of |{NiceArray}|, the user
-% must use the letters |L|, |C| and |R|\footnote{The column types |L|, |C| and |R| are defined locally inside
+% |columns-width| (explained below), |exterior-arraycolsep| and |parallelize-diags| (these last two options are
+% technical options described further). 
+% \item For technical reasons, in the preamble of the environment |{NiceArray}|, the user
+% must use the letters |L|, |C| and~|R|\footnote{The column types |L|, |C| and |R| are defined locally inside
 % |{NiceArray}| with |\newcolumntype| of \pkg{array}. This definition overrides an eventual previous definition.}
-% instead of |l|, |c| and |r|. It's possible to use the constructions \verb+|+, |>{...}|, |<{...}|, |@{...}|,
-% |!{...}| and |*{n}{...}| but the letters |p|, |m| and |b| should not be used.
+% instead of |l|, |c| and |r|. It's possible to use the constructions \verb|w{...}{...}|, \verb|W{...}{...}|,
+% \verb+|+, |>{...}|, |<{...}|, |@{...}|, |!{...}| and |*{n}{...}| but the letters |p|, |m| and |b| should not be used.
 % \end{itemize}
 %
 % 
@@ -475,6 +482,61 @@ version 2005/12/01 or later.
 % a_{n-1,1} & \Cdots & a_{n-1,n} \\
 % \end{NiceArray}\right)$
 %
+% \vskip1cm
+% As in the environment |{array}| of the extension \pkg{array}, it's possible to fix the width of a column by using
+% the letter |w| or the letter |W| in the preamble. In the following example, the width of the third column is
+% fixed to 1~cm.\par\nobreak
+% \medskip
+% \begin{BVerbatim}[baseline=c,boxwidth=10cm]
+% $\left(\begin{NiceArray}{CC~emphase#w{c}{1cm}@}
+% 1 & 2 & 3 \\
+% 4 & 5 & 6 \\
+% 7 & 8 & 9 
+% \end{NiceArray}\right)$
+% \end{BVerbatim}
+% $\left(\begin{NiceArray}{CCw{c}{1cm}}
+% 1 & 2 & 3 \\
+% 4 & 5 & 6 \\
+% 7 & 8 & 9 
+% \end{NiceArray}\right)$
+%
+% \bigskip
+% However, the environment |{NiceArray}| and the other environments defined in this extension have an option called
+% |columns-width| which fixes the width of all columns of the matrix.\par\nobreak
+% \medskip
+% \begin{BVerbatim}[baseline=c,boxwidth=10cm]
+% $\begin{pNiceMatrix}[~emphase#columns-width = 1cm@]
+% 1  & 12 & -123 \\
+% 12 & 0  & 0    \\
+% 4  & 1  & 2 
+% \end{pNiceMatrix}$
+% \end{BVerbatim}
+% $\begin{pNiceMatrix}[columns-width = 1cm]
+% 1  & 12 & -123 \\
+% 12 & 0  & 0    \\
+% 4  & 1  & 2 
+% \end{pNiceMatrix}$
+%
+% \medskip
+% Note that the space inserted between two columns (equal to 2 |\arraycolsep|) is not suppressed.
+%
+% \bigskip
+% It's also possible to give the value |auto| to the option |columns-width|: all the columns of the array will
+% have a width equal to the widest cell of the array. \emph{Two or three compilations may be necessary}.\par\nobreak
+% \medskip
+% \begin{BVerbatim}[baseline=c,boxwidth=10cm]
+% $\begin{pNiceMatrix}[~emphase#columns-width = auto@]
+% 1  & 12 & -123 \\
+% 12 & 0  & 0    \\
+% 4  & 1  & 2 
+% \end{pNiceMatrix}$
+% \end{BVerbatim}
+% $\left(\begin{NiceArray}[columns-width = auto]{CCC}
+% 1  & 12 & -123 \\
+% 12 & 0  & 0    \\
+% 4  & 1  & 2 
+% \end{NiceArray}\right)$
+%
 %
 % \section{The environment \{pNiceArrayC\} and its variants}
 %
@@ -492,15 +554,17 @@ version 2005/12/01 or later.
 % \item The environment |{pNiceArrayC}| takes a mandatory argument which is the preamble of the array. The types
 % of columns available are the same as for the environment |{NiceArray}|. \emph{However, no specification must be
 % given for the last column:} it will automatically (and necessarily) be a column~|L|. 
-% \item The options available are |renew-dots|, |nullify-dots|, |parallelize-diags| (this technical option is
-% described further) and |code-for-last-col|. This last option specifies tokens that will be inserted before each
+% \item The options available are |columns-width| (doesn't apply to the exterior column), |renew-dots|,
+% |nullify-dots|, |parallelize-diags| (this technical option is described further) and an option specific to these
+% environments, called |code-for-last-col|. This last option specifies tokens that will be inserted before each
 % cell of the last column, \emph{before} the symbol |$| of the math mode.
 % \end{itemize}
 % 
 % 
 % \bigskip
 % \begin{BVerbatim}[baseline=c]
-% \begin{pNiceArrayC}{RRRR|R}[~emphase#code-for-last-col={\small\color{blue}}@]
+% \begin{pNiceArrayC}{RRRR|R}[~emphase#code-for-last-col={\small\color{blue}}@,
+%                             columns-width=auto]
 % 1&  2&  2& 3& -2                      \\
 % 0&  0& -1& 5& -5 & L_2 \gets 2L_1-L_2 \\
 % 0& -1& -3& 3& -7 & L_3 \gets L_1-L_3  
@@ -508,7 +572,8 @@ version 2005/12/01 or later.
 % \end{BVerbatim}
 %
 % \smallskip
-% \[\begin{pNiceArrayC}{RRRR|R}[code-for-last-col={\small\color{blue}}]
+% \[\begin{pNiceArrayC}{RRRR|R}[code-for-last-col={\small\color{blue}},
+%                               columns-width=auto]
 % 1&  2&  2& 3& -2                      \\
 % 0&  0& -1& 5& -5 & L_2 \gets 2L_1-L_2 \\
 % 0& -1& -3& 3& -7 & L_3 \gets L_1-L_3  
@@ -795,6 +860,7 @@ version 2005/12/01 or later.
 % \bigskip
 % \subsection{Technical  definitions}
 %
+% 
 % First, we define a command |\iddots| similar to |\ddots| ($\ddots$) but with dots going forward ($\iddots$). We
 % use |\ProvideDocumentCommand| of \pkg{xparse}, and so, if the command |\iddots| has already been defined (for
 % example by the package \pkg{mathdots}), we don't define it again.
@@ -833,6 +899,12 @@ version 2005/12/01 or later.
 %    \end{macrocode}
 % 
 % \bigskip
+% The dimension |\l_@@_columns_width_dim| will be used when the options specify that all the columns must have the
+% same width.
+%    \begin{macrocode}
+\dim_new:N \l_@@_columns_width_dim
+%    \end{macrocode}
+% \bigskip
 % \subsection{The options}
 %
 % The token list |\l_@@_pos_env_tl| will contains one of the three values |t|, |c| or |b| and will indicate to
@@ -874,6 +946,14 @@ version 2005/12/01 or later.
 %    \end{macrocode}
 %
 % \bigskip
+% The following flag will be used when the current options specify that all the columns of the array must have the
+% same width equal to the largest width of a cell of the array (except the cell of the ``exterior column'' of an
+% environment of the kind of |{pNiceArrayC}|).
+%    \begin{macrocode}
+\bool_new:N \l_@@_auto_columns_width_bool
+%    \end{macrocode}
+% 
+% \bigskip
 % The token list |\l_@@_code_for_last_col_tl| will contains code inserted at the beginning of each cell\footnote{At
 % the beginning of each cell but before the character |$| of the mathematical mode.} of the last
 % column in the environment |{pNiceArrayC}| (and its variants). It corresponds to the option |code-for-last-col|.
@@ -925,6 +1005,7 @@ version 2005/12/01 or later.
       NullifyDots       .meta:n     = nullify-dots,
 %    \end{macrocode}
 %
+%
 % \bigskip
 % With the option |silent|, no error is generated for the impossible instructions. This option can be useful when
 % adapting an existing code. 
@@ -951,7 +1032,24 @@ version 2005/12/01 or later.
 %    \begin{macrocode}
       exterior-arraycolsep .bool_set:N = \l_@@_exterior_arraycolsep_bool ,
       exterior-arraycolsep .default:n  = true,
-      unknown .code:n  = \msg_error:nn {nicematrix} {Option~unknown}}
+      unknown .code:n  = \msg_error:nn {nicematrix} {Unknown~key~for~NiceMatrixOptions}}
+%    \end{macrocode}
+%
+%    \begin{macrocode}
+\msg_new:nnnn {nicematrix}
+              {Unknown~key~for~NiceMatrixOptions}
+              {The~key~"\tl_use:N\l_keys_key_tl"~is~unknown~for~the~command
+               \token_to_str:N \NiceMatrixOptions.\\
+               If~you~go~on,~it~will~be~ignored.\\
+               For~a~list~of~the~available~keys,~type~H~<return>.}
+              {The~available~keys~are~(in~alphabetic~order):~
+               code-for-last-col,~
+               exterior-arraycolsep,~
+               nullify-dots,~
+               parallelize-diags,~
+               renew-dots,~
+               renew-matrix~
+               and~transparent}
 %    \end{macrocode}
 % 
 % \bigskip
@@ -966,13 +1064,35 @@ version 2005/12/01 or later.
 % \bigskip
 %    \begin{macrocode}
 \keys_define:nn {NiceMatrix/NiceMatrix}
-     {parallelize-diags .bool_set:N = \l_@@_parallelize_diags_bool,
-      parallelize-diags .default:n  = true,
-      renew-dots        .bool_set:N = \l_@@_renew_dots_bool,
-      renew-dots        .default:n  = true,
-      nullify-dots      .bool_set:N = \l_@@_nullify_dots_bool ,
-      nullify-dots      .default:n  = true,
-      unknown .code:n  = \msg_error:nn {nicematrix} {Option~unknown}}
+     {parallelize-diags .bool_set:N  = \l_@@_parallelize_diags_bool,
+      parallelize-diags .default:n   = true,
+      renew-dots        .bool_set:N  = \l_@@_renew_dots_bool,
+      renew-dots        .default:n   = true,
+      nullify-dots      .bool_set:N  = \l_@@_nullify_dots_bool ,
+      nullify-dots      .default:n   = true,
+%    \end{macrocode}
+% The option |columns-width| is the width of the columns it we want the same width for all the columns of the
+% array. A value of 0~pt means that the width of the column will be the natural width of the column.
+%    \begin{macrocode}
+      columns-width     .code:n      = \str_if_eq:nnTF {#1} {auto}
+                                           {\bool_set_true:N 
+                                                \l_@@_auto_columns_width_bool}
+                                           {\dim_set:Nn \l_@@_columns_width_dim {#1}},
+      unknown .code:n  = \msg_error:nn {nicematrix} {Unknown~option~for~NiceMatrix}}
+%    \end{macrocode}
+%
+%    \begin{macrocode}
+\msg_new:nnnn {nicematrix}
+              {Unknown~option~for~NiceMatrix}
+              {The~option~"\tl_use:N\l_keys_key_tl"~is~unknown~for~the~environment~
+               \{NiceMatrix\}~and~its~variants.\\
+               If~you~go~on,~it~will~be~ignored.\\
+               For~a~list~of~the~available~options,~type~H~<return>.}
+              {The~available~options~are~(in~alphabetic~order):~
+               columns-width,~
+               nullify-dots,~
+               parallelize-diags~
+               and~renew-dots.}
 %    \end{macrocode}
 % 
 % \bigskip
@@ -986,6 +1106,10 @@ version 2005/12/01 or later.
       nullify-dots         .default:n  = true,
       exterior-arraycolsep .bool_set:N = \l_@@_exterior_arraycolsep_bool ,
       exterior-arraycolsep .default:n  = true,
+      columns-width        .code:n     = \str_if_eq:nnTF {#1} {auto}
+                                           {\bool_set_true:N \l_@@_auto_columns_width_bool}
+                                           {\dim_set:Nn \l_@@_columns_width_dim {#1}},
+      columns-width        .value_required:n = true,
 %    \end{macrocode}
 % 
 % \bigskip
@@ -995,9 +1119,26 @@ version 2005/12/01 or later.
       c .code:n = \tl_set:Nn \l_@@_pos_env_tl c,
       t .code:n = \tl_set:Nn \l_@@_pos_env_tl t,
       b .code:n = \tl_set:Nn \l_@@_pos_env_tl b,
-      unknown .code:n  = \msg_error:nn {nicematrix} {Option~unknown}}
+      unknown .code:n  = \msg_error:nn {nicematrix} {Unknown~option~for~NiceArray}}
 %    \end{macrocode}
 %
+%    \begin{macrocode}
+\msg_new:nnnn {nicematrix}
+              {Unknown~option~for~NiceArray}
+              {The~option~"\tl_use:N\l_keys_key_tl"~is~unknown~for~the~environment~
+               \{NiceArray\}.\\
+               If~you~go~on,~it~will~be~ignored.\\
+               For~a~list~of~the~available~options,~type~H~<return>.}
+              {The~available~options~are~(in~alphabetic~order):~
+               b,~
+               c,~
+               columns-width,~
+               exterior-arraycolsep,~
+               nullify-dots,~
+               parallelize-diags,~
+               renew-dots~
+               and~t.}
+%    \end{macrocode}
 % 
 % \bigskip
 % \subsection{The environments \{NiceArray\} and \{NiceMatrix\}}
@@ -1011,27 +1152,34 @@ version 2005/12/01 or later.
 % explanations).
 %    \begin{macrocode}
 \cs_new_protected:Nn \@@_Cell:n
-   { \tl_gput_right:Nn \g_@@_preamble_aux_tl {#1}
+   {\tl_gput_right:Nn \g_@@_preamble_aux_tl {#1}
 %    \end{macrocode}
 % We increment |\g_@@_column_int|, which is the counter of the columns. 
 %    \begin{macrocode}
     \int_gincr:N \g_@@_column_int
+    \hbox_set:Nw \l_tmpa_box $} % $
 %    \end{macrocode}
 % 
-% We create a Tikz node for the current cell of the array. 
 %    \begin{macrocode}
+\cs_new_protected:Nn \@@_end_Cell:
+   {$ % $ 
+    \hbox_set_end:
+%    \end{macrocode}
+% We want to compute in |\l_@@_max_cell_width_dim| the width of the widest cell of the array (except the cells of
+% the last column of an environment of the kind of |{pNiceArrayC}|).
+%    \begin{macrocode}
+    \dim_gset:Nn \g_@@_max_cell_width_dim
+          {\dim_max:nn \g_@@_max_cell_width_dim {\box_wd:N \l_tmpa_box}}
     \tikz[remember~picture, inner~sep = 0pt, minimum~width = 0pt, baseline]
        \node [anchor=base] (nm-\int_use:N \g_@@_env_int-
                                \int_use:N \g_@@_row_int-
                                \int_use:N \g_@@_column_int)
-       \bgroup $} % $
-%    \end{macrocode}
-%
-%    \begin{macrocode}
-\cs_new_protected:Nn \@@_end_Cell:
-   {$\egroup ;} % $
+       \bgroup 
+       \box_use:N \l_tmpa_box
+       \egroup ;} 
 %    \end{macrocode}
 %
+% 
 % \interitem
 % The environment |{NiceArray}| is the main environment of the extension \pkg{nicematrix}.
 %
@@ -1055,7 +1203,8 @@ version 2005/12/01 or later.
     {\keys_set:nn {NiceMatrix/NiceMatrix} {#1}
      \tl_set:Nn \l_@@_pos_env_tl c
      \bool_set_false:N \l_@@_exterior_arraycolsep_bool
-     \NiceArray{*\c@MaxMatrixCols{C}}}
+         \NiceArray{*\c@MaxMatrixCols{C}}
+      }
     {\endarray
      \skip_horizontal:n {-\arraycolsep}}
 %    \end{macrocode}
@@ -1069,10 +1218,29 @@ version 2005/12/01 or later.
 % \end{itemize}
 %               
 %    \begin{macrocode}
+\cs_generate_variant:Nn \dim_set:Nn {Nx}
 \NewDocumentEnvironment {NiceArray} {O{} m O{}}
-    {\aftergroup \@@_draw_lines:
+    {\aftergroup \@@_write_max_cell_width:
+     \aftergroup \@@_draw_lines:
+%    \end{macrocode}
+%
+% We increment the counter |\g_@@_env_int| which counts the environments |{NiceArray}|.
+%    \begin{macrocode}
+     \int_gincr:N \g_@@_env_int
+     \dim_gzero_new:N \g_@@_max_cell_width_dim
      \keys_set:nn {NiceMatrix/NiceArray} {#1,#3} 
 %    \end{macrocode}
+% 
+% If the user requires all the columns to have a width equal to the widest cell of the array, we read this length in
+% the file |.aux| (of, course, this is possible only on the second run of LaTeX : on the first run, the dimension
+% |\l_@@_columns_width_dim| will be set to zero --- and the columns will have their natural width).
+%    \begin{macrocode}
+     \bool_if:NT \l_@@_auto_columns_width_bool
+         {\cs_if_free:cTF {_@@_max_cell_width_\int_use:N \g_@@_env_int}
+             {\dim_set:Nn \l_@@_columns_width_dim \c_zero_dim}
+             {\dim_set:Nx \l_@@_columns_width_dim 
+                  {\use:c {_@@_max_cell_width_\int_use:N \g_@@_env_int}}}}
+%    \end{macrocode}
 % The environment |{array}| uses internally the command |\ialign| and, in particular, this command |\ialign| sets
 % |\everycr| to |{}|. However, we want to use |\everycr| in our array (in particular to increment |\g_@@_row_int|).
 % The solution is to give to |\ialign| a new definition (giving to |\everycr| the value we want)
@@ -1085,28 +1253,64 @@ version 2005/12/01 or later.
                              \int_gzero:N \g_@@_column_int
 %    \end{macrocode}
 % We want to have the preamble of the array in |\g_@@_preamble_tl| at the end of the array. However, some rows of the array
-% may be shorter (that is to say without all the ampersands) and it's not possible to known which row will be the
+% may be shorter (that is to say without all the ampersands) and it's not possible to know which row will be the
 % longest. That's why, during the construction of a row, we retrieve the corresponding preamble in
 % |\g_@@_preamble_aux_tl|. At the end of the array, we are sure that the longest value will be the real preamble of
 % the array (stored in |\g_@@_preamble_tl|).
 %    \begin{macrocode}                                                                                  
-                            \int_compare:nNnT {\tl_count:N \g_@@_preamble_aux_tl}
-                                            > {\tl_count:N \g_@@_preamble_tl} 
-                               {\tl_gset_eq:NN \g_@@_preamble_tl \g_@@_preamble_aux_tl}
-                            \tl_gclear:N \g_@@_preamble_aux_tl}}
+                             \int_compare:nNnT {\tl_count:N \g_@@_preamble_aux_tl}
+                                             > {\tl_count:N \g_@@_preamble_tl} 
+                                {\tl_gset_eq:NN \g_@@_preamble_tl \g_@@_preamble_aux_tl}
+                             \tl_gclear:N \g_@@_preamble_aux_tl}}
           \skip_zero:N \tabskip
           \cs_set:Npn \ialign {\everycr{} 
                                \skip_zero:N \tabskip
                                \halign}
           \halign}
 %    \end{macrocode}
+%                                                                                      
 % We define the new column types |L|, |C| and |R| that must be used instead of |l|, |c| and |r| in the preamble of
 % |{NiceArray}|.
 %    \begin{macrocode}
-     \newcolumntype{L}{>{\@@_Cell:n l}l<{\@@_end_Cell:}}
-     \newcolumntype{C}{>{\@@_Cell:n c}c<{\@@_end_Cell:}}
-     \newcolumntype{R}{>{\@@_Cell:n r}r<{\@@_end_Cell:}}
+     \dim_compare:nNnTF \l_@@_columns_width_dim = \c_zero_dim
+        {\newcolumntype{L}{>{\@@_Cell:n l}l<{\@@_end_Cell:}}
+         \newcolumntype{C}{>{\@@_Cell:n c}c<{\@@_end_Cell:}}
+         \newcolumntype{R}{>{\@@_Cell:n r}r<{\@@_end_Cell:}}}
+%    \end{macrocode}
+% If there is an option that specify that all the columns must have the same width, the column types~|L|, |C|
+% and~|R| are in fact defined upon the column type~|w| of array which is, in fact, redefined below.
+%    \begin{macrocode}
+        {\newcolumntype{L}{wl{\dim_use:N \l_@@_columns_width_dim}}
+         \newcolumntype{C}{wc{\dim_use:N \l_@@_columns_width_dim}}
+         \newcolumntype{R}{wr{\dim_use:N \l_@@_columns_width_dim}}}
+%    \end{macrocode}
+% 
+% We nullify the definitions of the column types |w| and |W| because we want to avoid a warning in the log file
+% for a redefinition of a column type.
+%    \begin{macrocode}
+     \cs_set_eq:NN \NC@find@w \relax
+     \cs_set_eq:NN \NC@find@W \relax
 %    \end{macrocode}
+% 
+% We redefine the column types |w| and |W| of the package \pkg{array}.
+%    \begin{macrocode}
+     \newcolumntype{w}[2]
+       {>{\hbox_set:Nw \l_tmpa_box
+          \@@_Cell:n ##1}
+        c
+        <{\@@_end_Cell:
+          \hbox_set_end:
+          \makebox[##2][##1]{\box_use:N \l_tmpa_box}}}
+     \newcolumntype{W}[2]
+       {>{\hbox_set:Nw \l_tmpa_box
+          \@@_Cell:n ##1}
+        c
+        <{\@@_end_Cell:
+          \hbox_set_end:
+          \cs_set_eq:NN \hss \hfil
+          \makebox[##2][##1]{\box_use:N \l_tmpa_box}}}
+%    \end{macrocode}
+% 
 % The commands |\Ldots|, |\Cdots|, etc. will be defined only in the environment |{NiceArray}|.
 %    \begin{macrocode}
      \cs_set_eq:NN \Ldots \@@_Ldots
@@ -1126,10 +1330,6 @@ version 2005/12/01 or later.
        {\cs_set_eq:NN \multicolumn \@@_multicolumn:nn}
 %    \end{macrocode}
 % 
-% We increment the counter |\g_@@_env_int| which counts the environments |{NiceArray}|.
-%    \begin{macrocode}
-     \int_gincr:N \g_@@_env_int
-%    \end{macrocode}
 %
 % We have to remind the types of the columns (|l|, |c| or |r|) because we will use this information when we will
 % draw the vertical dotted lines. That's why we store the types of the columns in |\g_@@_preamble_tl| (for example,
@@ -1222,6 +1422,20 @@ version 2005/12/01 or later.
 %    \end{macrocode}
 %
 % \interitem
+% For the option \verb|columns-width=auto|, we want to known the maximal width of the cells of the array (except
+% the cells of the ``exterior'' column of an environment of the kind of |{pNiceAccayC}|). This length can be known
+% only after the end of the construction of the array: that's why we store this value in the main |.aux| file and
+% it will be available in the next run. 
+%    \begin{macrocode}
+\cs_new:Nn \@@_write_max_cell_width:
+      {\iow_now:Nx \@mainaux 
+        {\ExplSyntaxOn
+           \cs_gset:cpn {_@@_max_cell_width_\int_use:N \g_@@_env_int} 
+                        {\dim_use:N \g_@@_max_cell_width_dim}
+         \ExplSyntaxOff}}
+%    \end{macrocode}
+% 
+% \interitem
 % The conditionnal |\@@_if_not_empty_cell:nnT| test wether a cell is empty. The first two arguments must be LaTeX3
 % counters for the row and the column of the considered cell.
 %    \begin{macrocode}
@@ -1849,13 +2063,6 @@ version 2005/12/01 or later.
               \token_to_str:N \multicolumn.~You~can~go~on~but~your~line~will~
               probably~be~wrong.}
 %    \end{macrocode}
-%
-%    \begin{macrocode}
-\msg_new:nnn {nicematrix}
-             {Option~unknown}
-             {The~option~"\tl_use:N\l_keys_key_tl"~is~unknown~or~
-              meaningless~in~the~context.~If~you~go~on,~it~will~be~ignored.}
-%    \end{macrocode}
 % 
 % \bigskip
 % \subsection{The environment \{pNiceArrayC\} and its variants}
@@ -1868,15 +2075,35 @@ version 2005/12/01 or later.
 %
 %    \begin{macrocode}
 \keys_define:nn {NiceMatrix/NiceArrayC}
-     {parallelize-diags    .bool_set:N       = \l_@@_parallelize_diags_bool,
-      parallelize-diags    .default:n        = true,
-      renew-dots           .bool_set:N       = \l_@@_renew_dots_bool,
-      renew-dots           .default:n        = true,
-      nullify-dots         .bool_set:N       = \l_@@_nullify_dots_bool ,
-      nullify-dots         .default:n        = true,
-      code-for-last-col    .tl_set:N         = \l_@@_code_for_last_col_tl,
-      code-for-last-col    .value_required:n = true,
-      unknown .code:n  = \msg_error:nn {nicematrix} {Option~unknown}}
+     {parallelize-diags .bool_set:N       = \l_@@_parallelize_diags_bool,
+      parallelize-diags .default:n        = true,
+      renew-dots        .bool_set:N       = \l_@@_renew_dots_bool,
+      renew-dots        .default:n        = true,
+      nullify-dots      .bool_set:N       = \l_@@_nullify_dots_bool ,
+      nullify-dots      .default:n        = true,
+      code-for-last-col .tl_set:N         = \l_@@_code_for_last_col_tl,
+      code-for-last-col .value_required:n = true,
+      columns-width     .code:n           = \str_if_eq:nnTF {#1} {auto}
+                                            {\bool_set_true:N 
+                                                   \l_@@_auto_columns_width_bool}
+                                            {\dim_set:Nn \l_@@_columns_width_dim {#1}},
+      columns-width     .value_required:n = true,
+      unknown .code:n  = \msg_error:nn {nicematrix} {Unknown~option~for~pNiceArrayC}}
+%    \end{macrocode}
+%
+%    \begin{macrocode}
+\msg_new:nnnn {nicematrix}
+              {Unknown~option~for~pNiceArrayC}
+              {The~option~"\tl_use:N\l_keys_key_tl"~is~unknown~for~the~environment~
+               \{\@currenvir\}.\\
+               If~you~go~on,~it~will~be~ignored.\\
+               For~a~list~of~the~available~options,~type~H~<return>.}
+              {The~available~options~are~(in~alphabetic~order):~
+               code-for-last-col,~
+               columns-width,~
+               nullify-dots,~
+               parallelize-diags~
+               and~renew-dots.}
 %    \end{macrocode}
 %
 % \bigskip
@@ -1904,20 +2131,28 @@ version 2005/12/01 or later.
 % to store the content of the cell in the box |\l_tmpa_box|. This is allowed in \pkg{expl3} with the construction
 % |\hbox_set:Nw \l_tmpa_box| ... |\hbox_set_end:|.
 %    \begin{macrocode}
-                >{\hbox_set:Nw \l_tmpa_box 
+                >{\int_gincr:N \g__nm_column_int
+                  \hbox_set:Nw \l_tmpa_box 
                   \l_@@_code_for_last_col_tl
-                  \@@_Cell:n l}
-                  l
-                <{\@@_end_Cell:
-                  \hbox_set_end:
+                  \tikz[remember~picture, inner~sep = 0pt, minimum~width = 0pt, baseline]
+                     \node [anchor=base] (nm-\int_use:N \g__nm_env_int-
+                                             \int_use:N \g__nm_row_int-
+                                             \int_use:N \g__nm_column_int)
+                     \bgroup $ % $ 
+                 }
+                l
 %    \end{macrocode}
 % 
 % We actualize the value of |\g_@@with_last_col_dim| which, at the end of the array, will contains the maximal width
 % of the cells of the last column (thus, it will be equal to the width of the last column).
 %    \begin{macrocode}
+                <{   $ % $
+                     \egroup ;
+                  \hbox_set_end:
                   \dim_gset:Nn \g_@@_width_last_col_dim
                      {\dim_max:nn \g_@@_width_last_col_dim
                                   {\box_wd:N \l_tmpa_box}}
+                  \tl_gput_right:Nn \g__nm_preamble_aux_tl {#1}
                   \skip_horizontal:n {-2\arraycolsep}
 %    \end{macrocode}
 % The content of the cell is inserted in a overlapping position.
@@ -1976,7 +2211,7 @@ version 2005/12/01 or later.
      \@@_after_last_col:}
 %    \end{macrocode}
 %
-%
+% 
 %                           
 % \section{History}
 %
@@ -2007,6 +2242,13 @@ version 2005/12/01 or later.
 % hyphens (but backward compatibility is kept).
 % 
 %
+% \subsection{Changes between version 1.3 and 1.4}
+% 
+% The column types |w| and |W| can now be used in the environments |{NiceArray}|, |{pNiceArrayC}| and its variants
+% with the same meaning as in the package \pkg{array}.
+% 
+% New option |columns-width| to fix the same width for all the columns of the array.
+% 
 % \endinput
 % Local Variables:
 % TeX-fold-mode: nil
diff --git a/Master/texmf-dist/tex/latex/nicematrix/nicematrix.sty b/Master/texmf-dist/tex/latex/nicematrix/nicematrix.sty
index fa0c20dbd66..ca85ddf7d2b 100644
--- a/Master/texmf-dist/tex/latex/nicematrix/nicematrix.sty
+++ b/Master/texmf-dist/tex/latex/nicematrix/nicematrix.sty
@@ -18,8 +18,8 @@
 %% and version 1.3 or later is part of all distributions of
 %% LaTeX version 2005/12/01 or later.
 %% 
-\def\myfileversion{1.3}
-\def\myfiledate{2018/03/31}
+\def\myfileversion{1.4}
+\def\myfiledate{2018/04/16}
 \RequirePackage{l3keys2e}
 \ProvidesExplPackage
   {nicematrix}
@@ -42,6 +42,7 @@
 \cs_new_protected:Nn \__nm_multicolumn:nn
        {\msg_error:nn {nicematrix} {Multicolumn~forbidden}}
 \int_new:N \g__nm_env_int
+\dim_new:N \l__nm_columns_width_dim
 \tl_new:N \l__nm_pos_env_tl
 \tl_set:Nn \l__nm_pos_env_tl c
 \bool_new:N \l__nm_exterior_arraycolsep_bool
@@ -49,6 +50,7 @@
 \bool_set_true:N \l__nm_parallelize_diags_bool
 \bool_new:N \l__nm_nullify_dots_bool
 \bool_new:N \l__nm_renew_matrix_bool
+\bool_new:N \l__nm_auto_columns_width_bool
 \tl_new:N \l__nm_code_for_last_col_tl
 \keys_define:nn {NiceMatrix/NiceMatrixOptions}
      {parallelize-diags    .bool_set:N = \l__nm_parallelize_diags_bool,
@@ -76,17 +78,46 @@
       code-for-last-col  .value_required:n = true,
       exterior-arraycolsep .bool_set:N = \l__nm_exterior_arraycolsep_bool ,
       exterior-arraycolsep .default:n  = true,
-      unknown .code:n  = \msg_error:nn {nicematrix} {Option~unknown}}
+      unknown .code:n  = \msg_error:nn {nicematrix} {Unknown~key~for~NiceMatrixOptions}}
+\msg_new:nnnn {nicematrix}
+              {Unknown~key~for~NiceMatrixOptions}
+              {The~key~"\tl_use:N\l_keys_key_tl"~is~unknown~for~the~command
+               \token_to_str:N \NiceMatrixOptions.\\
+               If~you~go~on,~it~will~be~ignored.\\
+               For~a~list~of~the~available~keys,~type~H~<return>.}
+              {The~available~keys~are~(in~alphabetic~order):~
+               code-for-last-col,~
+               exterior-arraycolsep,~
+               nullify-dots,~
+               parallelize-diags,~
+               renew-dots,~
+               renew-matrix~
+               and~transparent}
 \NewDocumentCommand \NiceMatrixOptions {m}
     {\keys_set:nn {NiceMatrix/NiceMatrixOptions} {#1}}
 \keys_define:nn {NiceMatrix/NiceMatrix}
-     {parallelize-diags .bool_set:N = \l__nm_parallelize_diags_bool,
-      parallelize-diags .default:n  = true,
-      renew-dots        .bool_set:N = \l__nm_renew_dots_bool,
-      renew-dots        .default:n  = true,
-      nullify-dots      .bool_set:N = \l__nm_nullify_dots_bool ,
-      nullify-dots      .default:n  = true,
-      unknown .code:n  = \msg_error:nn {nicematrix} {Option~unknown}}
+     {parallelize-diags .bool_set:N  = \l__nm_parallelize_diags_bool,
+      parallelize-diags .default:n   = true,
+      renew-dots        .bool_set:N  = \l__nm_renew_dots_bool,
+      renew-dots        .default:n   = true,
+      nullify-dots      .bool_set:N  = \l__nm_nullify_dots_bool ,
+      nullify-dots      .default:n   = true,
+      columns-width     .code:n      = \str_if_eq:nnTF {#1} {auto}
+                                           {\bool_set_true:N
+                                                \l__nm_auto_columns_width_bool}
+                                           {\dim_set:Nn \l__nm_columns_width_dim {#1}},
+      unknown .code:n  = \msg_error:nn {nicematrix} {Unknown~option~for~NiceMatrix}}
+\msg_new:nnnn {nicematrix}
+              {Unknown~option~for~NiceMatrix}
+              {The~option~"\tl_use:N\l_keys_key_tl"~is~unknown~for~the~environment~
+               \{NiceMatrix\}~and~its~variants.\\
+               If~you~go~on,~it~will~be~ignored.\\
+               For~a~list~of~the~available~options,~type~H~<return>.}
+              {The~available~options~are~(in~alphabetic~order):~
+               columns-width,~
+               nullify-dots,~
+               parallelize-diags~
+               and~renew-dots.}
 \keys_define:nn {NiceMatrix/NiceArray}
      {parallelize-diags    .bool_set:N = \l__nm_parallelize_diags_bool,
       parallelize-diags    .default:n  = true,
@@ -96,45 +127,101 @@
       nullify-dots         .default:n  = true,
       exterior-arraycolsep .bool_set:N = \l__nm_exterior_arraycolsep_bool ,
       exterior-arraycolsep .default:n  = true,
+      columns-width        .code:n     = \str_if_eq:nnTF {#1} {auto}
+                                           {\bool_set_true:N \l__nm_auto_columns_width_bool}
+                                           {\dim_set:Nn \l__nm_columns_width_dim {#1}},
+      columns-width        .value_required:n = true,
       c .code:n = \tl_set:Nn \l__nm_pos_env_tl c,
       t .code:n = \tl_set:Nn \l__nm_pos_env_tl t,
       b .code:n = \tl_set:Nn \l__nm_pos_env_tl b,
-      unknown .code:n  = \msg_error:nn {nicematrix} {Option~unknown}}
+      unknown .code:n  = \msg_error:nn {nicematrix} {Unknown~option~for~NiceArray}}
+\msg_new:nnnn {nicematrix}
+              {Unknown~option~for~NiceArray}
+              {The~option~"\tl_use:N\l_keys_key_tl"~is~unknown~for~the~environment~
+               \{NiceArray\}.\\
+               If~you~go~on,~it~will~be~ignored.\\
+               For~a~list~of~the~available~options,~type~H~<return>.}
+              {The~available~options~are~(in~alphabetic~order):~
+               b,~
+               c,~
+               columns-width,~
+               exterior-arraycolsep,~
+               nullify-dots,~
+               parallelize-diags,~
+               renew-dots~
+               and~t.}
 \cs_new_protected:Nn \__nm_Cell:n
-   { \tl_gput_right:Nn \g__nm_preamble_aux_tl {#1}
+   {\tl_gput_right:Nn \g__nm_preamble_aux_tl {#1}
     \int_gincr:N \g__nm_column_int
+    \hbox_set:Nw \l_tmpa_box $} % $
+\cs_new_protected:Nn \__nm_end_Cell:
+   {$ % $
+    \hbox_set_end:
+    \dim_gset:Nn \g__nm_max_cell_width_dim
+          {\dim_max:nn \g__nm_max_cell_width_dim {\box_wd:N \l_tmpa_box}}
     \tikz[remember~picture, inner~sep = 0pt, minimum~width = 0pt, baseline]
        \node [anchor=base] (nm-\int_use:N \g__nm_env_int-
                                \int_use:N \g__nm_row_int-
                                \int_use:N \g__nm_column_int)
-       \bgroup $} % $
-\cs_new_protected:Nn \__nm_end_Cell:
-   {$\egroup ;} % $
+       \bgroup
+       \box_use:N \l_tmpa_box
+       \egroup ;}
 \NewDocumentEnvironment {NiceMatrix} {O{}}
     {\keys_set:nn {NiceMatrix/NiceMatrix} {#1}
      \tl_set:Nn \l__nm_pos_env_tl c
      \bool_set_false:N \l__nm_exterior_arraycolsep_bool
-     \NiceArray{*\c@MaxMatrixCols{C}}}
+         \NiceArray{*\c@MaxMatrixCols{C}}
+      }
     {\endarray
      \skip_horizontal:n {-\arraycolsep}}
+\cs_generate_variant:Nn \dim_set:Nn {Nx}
 \NewDocumentEnvironment {NiceArray} {O{} m O{}}
-    {\aftergroup \__nm_draw_lines:
+    {\aftergroup \__nm_write_max_cell_width:
+     \aftergroup \__nm_draw_lines:
+     \int_gincr:N \g__nm_env_int
+     \dim_gzero_new:N \g__nm_max_cell_width_dim
      \keys_set:nn {NiceMatrix/NiceArray} {#1,#3}
+     \bool_if:NT \l__nm_auto_columns_width_bool
+         {\cs_if_free:cTF {__nm_max_cell_width_\int_use:N \g__nm_env_int}
+             {\dim_set:Nn \l__nm_columns_width_dim \c_zero_dim}
+             {\dim_set:Nx \l__nm_columns_width_dim
+                  {\use:c {__nm_max_cell_width_\int_use:N \g__nm_env_int}}}}
      \cs_set:Npn \ialign
           {\everycr{\noalign{\int_gincr:N \g__nm_row_int
                              \int_gzero:N \g__nm_column_int
-                            \int_compare:nNnT {\tl_count:N \g__nm_preamble_aux_tl}
-                                            > {\tl_count:N \g__nm_preamble_tl}
-                               {\tl_gset_eq:NN \g__nm_preamble_tl \g__nm_preamble_aux_tl}
-                            \tl_gclear:N \g__nm_preamble_aux_tl}}
+                             \int_compare:nNnT {\tl_count:N \g__nm_preamble_aux_tl}
+                                             > {\tl_count:N \g__nm_preamble_tl}
+                                {\tl_gset_eq:NN \g__nm_preamble_tl \g__nm_preamble_aux_tl}
+                             \tl_gclear:N \g__nm_preamble_aux_tl}}
           \skip_zero:N \tabskip
           \cs_set:Npn \ialign {\everycr{}
                                \skip_zero:N \tabskip
                                \halign}
           \halign}
-     \newcolumntype{L}{>{\__nm_Cell:n l}l<{\__nm_end_Cell:}}
-     \newcolumntype{C}{>{\__nm_Cell:n c}c<{\__nm_end_Cell:}}
-     \newcolumntype{R}{>{\__nm_Cell:n r}r<{\__nm_end_Cell:}}
+     \dim_compare:nNnTF \l__nm_columns_width_dim = \c_zero_dim
+        {\newcolumntype{L}{>{\__nm_Cell:n l}l<{\__nm_end_Cell:}}
+         \newcolumntype{C}{>{\__nm_Cell:n c}c<{\__nm_end_Cell:}}
+         \newcolumntype{R}{>{\__nm_Cell:n r}r<{\__nm_end_Cell:}}}
+        {\newcolumntype{L}{wl{\dim_use:N \l__nm_columns_width_dim}}
+         \newcolumntype{C}{wc{\dim_use:N \l__nm_columns_width_dim}}
+         \newcolumntype{R}{wr{\dim_use:N \l__nm_columns_width_dim}}}
+     \cs_set_eq:NN \NC@find@w \relax
+     \cs_set_eq:NN \NC@find@W \relax
+     \newcolumntype{w}[2]
+       {>{\hbox_set:Nw \l_tmpa_box
+          \__nm_Cell:n ##1}
+        c
+        <{\__nm_end_Cell:
+          \hbox_set_end:
+          \makebox[##2][##1]{\box_use:N \l_tmpa_box}}}
+     \newcolumntype{W}[2]
+       {>{\hbox_set:Nw \l_tmpa_box
+          \__nm_Cell:n ##1}
+        c
+        <{\__nm_end_Cell:
+          \hbox_set_end:
+          \cs_set_eq:NN \hss \hfil
+          \makebox[##2][##1]{\box_use:N \l_tmpa_box}}}
      \cs_set_eq:NN \Ldots \__nm_Ldots
      \cs_set_eq:NN \Cdots \__nm_Cdots
      \cs_set_eq:NN \Vdots \__nm_Vdots
@@ -150,7 +237,6 @@
          \cs_set_eq:NN \iddots \__nm_Iddots}
      \bool_if:NF \l__nm_renew_matrix_bool
        {\cs_set_eq:NN \multicolumn \__nm_multicolumn:nn}
-     \int_gincr:N \g__nm_env_int
      \tl_clear_new:N \g__nm_preamble_tl
      \tl_clear_new:N \g__nm_preamble_aux_tl
      \seq_gclear_new:N  \g__nm_empty_cells_seq
@@ -179,6 +265,12 @@
 \NewDocumentEnvironment {VNiceMatrix} {}
    {\left\lVert\begin{NiceMatrix}}
    {\end{NiceMatrix}\right\rVert}
+\cs_new:Nn \__nm_write_max_cell_width:
+      {\iow_now:Nx \@mainaux
+        {\ExplSyntaxOn
+           \cs_gset:cpn {__nm_max_cell_width_\int_use:N \g__nm_env_int}
+                        {\dim_use:N \g__nm_max_cell_width_dim}
+         \ExplSyntaxOff}}
 \prg_set_conditional:Npnn \__nm_if_not_empty_cell:nn #1#2 {T}
        {\cs_if_exist:cTF {pgf@sh@ns@nm-\int_use:N \g__nm_env_int-
                                        \int_use:N #1-
@@ -465,20 +557,33 @@
               of~amsmath~is~also~forbidden~since~it~uses~
               \token_to_str:N \multicolumn.~You~can~go~on~but~your~line~will~
               probably~be~wrong.}
-\msg_new:nnn {nicematrix}
-             {Option~unknown}
-             {The~option~"\tl_use:N\l_keys_key_tl"~is~unknown~or~
-              meaningless~in~the~context.~If~you~go~on,~it~will~be~ignored.}
 \keys_define:nn {NiceMatrix/NiceArrayC}
-     {parallelize-diags    .bool_set:N       = \l__nm_parallelize_diags_bool,
-      parallelize-diags    .default:n        = true,
-      renew-dots           .bool_set:N       = \l__nm_renew_dots_bool,
-      renew-dots           .default:n        = true,
-      nullify-dots         .bool_set:N       = \l__nm_nullify_dots_bool ,
-      nullify-dots         .default:n        = true,
-      code-for-last-col    .tl_set:N         = \l__nm_code_for_last_col_tl,
-      code-for-last-col    .value_required:n = true,
-      unknown .code:n  = \msg_error:nn {nicematrix} {Option~unknown}}
+     {parallelize-diags .bool_set:N       = \l__nm_parallelize_diags_bool,
+      parallelize-diags .default:n        = true,
+      renew-dots        .bool_set:N       = \l__nm_renew_dots_bool,
+      renew-dots        .default:n        = true,
+      nullify-dots      .bool_set:N       = \l__nm_nullify_dots_bool ,
+      nullify-dots      .default:n        = true,
+      code-for-last-col .tl_set:N         = \l__nm_code_for_last_col_tl,
+      code-for-last-col .value_required:n = true,
+      columns-width     .code:n           = \str_if_eq:nnTF {#1} {auto}
+                                            {\bool_set_true:N
+                                                   \l__nm_auto_columns_width_bool}
+                                            {\dim_set:Nn \l__nm_columns_width_dim {#1}},
+      columns-width     .value_required:n = true,
+      unknown .code:n  = \msg_error:nn {nicematrix} {Unknown~option~for~pNiceArrayC}}
+\msg_new:nnnn {nicematrix}
+              {Unknown~option~for~pNiceArrayC}
+              {The~option~"\tl_use:N\l_keys_key_tl"~is~unknown~for~the~environment~
+               \{\@currenvir\}.\\
+               If~you~go~on,~it~will~be~ignored.\\
+               For~a~list~of~the~available~options,~type~H~<return>.}
+              {The~available~options~are~(in~alphabetic~order):~
+               code-for-last-col,~
+               columns-width,~
+               nullify-dots,~
+               parallelize-diags~
+               and~renew-dots.}
 \cs_new_protected:Nn \__nm_NiceArrayC:nn
     {\dim_gzero_new:N \g__nm_width_last_col_dim
      \keys_set:nn {NiceMatrix/NiceArrayC} {#1}
@@ -486,15 +591,23 @@
      \tl_set:Nn \l__nm_pos_env_tl c
      \begin{NiceArray}
              {#2
-                >{\hbox_set:Nw \l_tmpa_box
+                >{\int_gincr:N \g__nm_column_int
+                  \hbox_set:Nw \l_tmpa_box
                   \l__nm_code_for_last_col_tl
-                  \__nm_Cell:n l}
-                  l
-                <{\__nm_end_Cell:
+                  \tikz[remember~picture, inner~sep = 0pt, minimum~width = 0pt, baseline]
+                     \node [anchor=base] (nm-\int_use:N \g__nm_env_int-
+                                             \int_use:N \g__nm_row_int-
+                                             \int_use:N \g__nm_column_int)
+                     \bgroup $ % $
+                 }
+                l
+                <{   $ % $
+                     \egroup ;
                   \hbox_set_end:
                   \dim_gset:Nn \g__nm_width_last_col_dim
                      {\dim_max:nn \g__nm_width_last_col_dim
                                   {\box_wd:N \l_tmpa_box}}
+                  \tl_gput_right:Nn \g__nm_preamble_aux_tl {#1}
                   \skip_horizontal:n {-2\arraycolsep}
                   \hbox_overlap_right:n
                        {\skip_horizontal:n {2\arraycolsep}