在环境选项列表中扩展宏

Question 1

如果所有 key=value 内容都可以完全扩展，则可以使用在-environment 读取\expanded之前对其进行扩展。然后，您应该保护不进行扩展（使用下面的代码中的，或用不应进一步扩展的内容替换）。tblr\begin\noexpand\unexpanded{<stuff>}<stuff>

正如我在评论中指出的那样，TeX 中的参数是一组单独的括号，因此应该用\newcell{4}{4}{4}代替\newcell{4, 4, 4}。此外，的参数数量\newcommand在括号中给出，而不是括号，因为这是一个可选参数：\newcommand{\newcell}[3]{<replacement text>}。

应用这些内容后，您的代码将变为以下形式：

\documentclass[preview]{standalone}

\usepackage{tabularray}

% previous parameter definition, does not scale
\def\cellax{1}
\def\cellay{2}
\def\cellaw{4}

\def\cellbx{2}
\def\cellby{3}
\def\cellbw{5}

% want to use a macro taking arguments
\newcommand{\newcell}[3]{
    hline{#2-{#2+1}}={#1-{#1 + #3 - 1}}{solid},
    vline{#1,#1+#3}={#2}{solid},
    cell{#2}{#1}={c=#3}{c},
}

\begin{document}
\begin{table}[!ht]
    \ttfamily
    \centering
    $\expanded{\noexpand\begin{tblr}{
        hline{1}={1-Z}{solid},
        hline{2}={1-Z}{solid},
        vline{1}={1}{solid},
        vline{2-11}={1}{dashed},
        %
        hline{\cellay-{\cellay+1}}={\cellax-{\cellax + \cellaw - 1}}{solid},
        vline{\cellax,\cellax+\cellaw}={\cellay}{solid},
        cell{\cellay}{\cellax}={c=\cellaw}{c},
        %
        hline{\cellby-{\cellby+1}}={\cellbx-{\cellbx + \cellbw - 1}}{solid},
        vline{\cellbx,\cellbx+\cellbw}={\cellby}{solid},
        cell{\cellby}{\cellbx}={c=\cellbw}{c},
        % Want to use it here ....
        \newcell{4}{4}{4},
        %
        hspan = even,
    }}
    x_1&x_2&x_3&x_4&x_5&x_6&x_7&x_8&x_9&x_{10}&\ldots\\
    n_1&\\
    &n_2  \\ 
    &&n_3  \\ 
    &&&&\ddots  \\ 
    \end{tblr}$
\end{table}
\end{document}

提供更多控制的替代方法是使用expkv¹及其 key=value-expansion 语法。在下面的前面，V:指示\newcell扩展expkv以下内容一次（如果它有，=它将扩展值而不是键）。其他所有内容均原封不动地转发（或至少几乎原封不动，键名周围的一组外括号将被剥离 - 您的 MWE 中不存在）。

为了简化将键列表包装到expkv扩展机制中的工作，我编写了一个简短的辅助宏\keyexpander。如果您需要解释，请直接询问。

\documentclass[preview]{standalone}

\usepackage{tabularray}
\usepackage{expkv-cs}

\newcommand*\keyexpander{\ekvoptarg\keyexpanderKV{}}
\ekvcSplitAndForward\keyexpanderKV\keyexpanderDO
  {
     pre = {}
    ,post = {}
    ,keyProc  = \keyexpanderKEY
    ,pairProc = \keyexpanderPAIR
  }
\ekvcSecondaryKeys\keyexpanderKV
  {
     nmeta oarg = { pre = [, post = ] }
    ,nmeta brace-keys =
      { keyProc = \keyexpanderKEYBR, pairProc = \keyexpanderPAIRBR }
    ,nmeta plain-keys =
      { keyProc = \keyexpanderKEY, pairProc = \keyexpanderPAIR }
  }
\newcommand\keyexpanderDO[6]
  {%
    \expanded
      {%
        \unexpanded{#5#1}%
        {%
          \IfBlankF{#6}
            {%
              \unexpanded\expandafter\expandafter\expandafter
                {%
                  \expandafter\keyexpanderCOMMA\expanded
                    {\expanded{\ekvparse{#3}{#4}{#6}}}%
                }%
            }%
        }%
      }%
    #2%
  }
\def\keyexpanderCOMMA, {}
\newcommand\keyexpanderKEY[1]{, \unexpanded{#1}}
\newcommand\keyexpanderPAIR[2]{, \unexpanded{#1}= {\unexpanded{#2}}}
\newcommand\keyexpanderKEYBR[1]{, {\unexpanded{#1}}}
\newcommand\keyexpanderPAIRBR[2]{, {\unexpanded{#1}}= {\unexpanded{#2}}}

% previous parameter definition, does not scale
\def\cellax{1}
\def\cellay{2}
\def\cellaw{4}

\def\cellbx{2}
\def\cellby{3}
\def\cellbw{5}

% want to use a macro taking arguments
\newcommand{\newcell}[3]{
    hline{#2-{#2+1}}={#1-{#1 + #3 - 1}}{solid},
    vline{#1,#1+#3}={#2}{solid},
    cell{#2}{#1}={c=#3}{c},
}

\begin{document}
\begin{table}[!ht]
    \ttfamily
    \centering
    $\keyexpander{\begin{tblr}}{
        hline{1}={1-Z}{solid},
        hline{2}={1-Z}{solid},
        vline{1}={1}{solid},
        vline{2-11}={1}{dashed},
        %
        hline{\cellay-{\cellay+1}}={\cellax-{\cellax + \cellaw - 1}}{solid},
        vline{\cellax,\cellax+\cellaw}={\cellay}{solid},
        cell{\cellay}{\cellax}={c=\cellaw}{c},
        %
        hline{\cellby-{\cellby+1}}={\cellbx-{\cellbx + \cellbw - 1}}{solid},
        vline{\cellbx,\cellbx+\cellbw}={\cellby}{solid},
        cell{\cellby}{\cellbx}={c=\cellbw}{c},
        % Want to use it here ....
        V: \newcell{4}{4}{4},
        %
        hspan = even,
      }
    x_1&x_2&x_3&x_4&x_5&x_6&x_7&x_8&x_9&x_{10}&\ldots\\
    n_1&\\
    &n_2  \\ 
    &&n_3  \\ 
    &&&&\ddots  \\ 
    \end{tblr}$
\end{table}
\end{document}

输出如上。

_{¹免责声明：我是的作者expkv。}

Answer