将短行或长行对齐到完美的矩形段落

Question

这种方法半-automatic，因为仍然必须将段落括在\fixit宏中。

修订方法

我不是像下面的原始方法那样逐字逐句地剖析段落，而是在这里，我只测量包含段落材料的长度\hbox，然后根据长度决定是否使用尾随\hspace{}\mbox和/或\parfillskip0pt。

如果需要调整，该宏会提供一个可选参数。它表示将被压缩掉的最大分数行超限，当前设置为.05(5%)。如果您认为会被压缩掉的一行被扩展为一个全新的宽间距行，您就会知道它需要调整。将默认值设置为.0将消除任何问题，但代价是一些原本可以压缩以消除尾随寡妇的行被扩展，使得寡妇占据后续行的 20%。

\documentclass{article}
\usepackage[margin=1.5in,top=0cm,bottom=0cm]{geometry}
\newcommand\fixit[2][.05]{%
  \setbox0=\hbox{\hspace{\parindent}#2}\fixithelp{#1}{#2}}
\newcommand\fixithelp[2]{%
  \wd0=\dimexpr\wd0-\linewidth\relax%
  \ifdim\wd0>0pt\relax%
    \fixithelp{#1}{#2}%
  \else%
    \wd0=\dimexpr\wd0+\linewidth\relax
    \ifdim\wd0>.9\linewidth\relax%
      {\parfillskip0pt\relax#2\par}%
    \else%
      \ifdim\wd0>.8\linewidth\relax%
        {\parfillskip0pt\relax#2\hspace{.2\linewidth}\par}%
      \else%
        \ifdim\wd0<#1\linewidth\relax%
          {\parfillskip0pt\relax#2\par}%
        \else%
          \ifdim\wd0<.2\linewidth\relax%
            {\parfillskip0pt\relax#2\hspace{.8\linewidth}\mbox{}\par}%
          \else%
            #2%
          \fi
        \fi
      \fi
    \fi
  \fi%
}
\sloppy
\parskip1ex
\begin{document}
\noindent\rule{.2\linewidth}{2pt}\hfill\rule{.2\linewidth}{2pt}

\fixit{%
yakity yack, paragraphs, I want to \textit{ensure their last line} is neither 
overly short nor overly long. To that end, I'm looking for settings that 
produce either:}

\fixit{%
yack, yakity yack, paragraphs, I want to \textit{ensure their last line} is neither 
overly short nor overly long. To that end, I'm looking for settings that 
produce either:}

\fixit{%
yakity yack, yakity yack, paragraphs, I want to \textit{ensure their last line} is neither 
overly short nor overly long. To that end, I'm looking for settings that 
produce either:}

\fixit{%
yack, yakity yack, yakity yack, paragraphs, I want to \textit{ensure their last line} is neither 
overly short nor overly long. To that end, I'm looking for settings that 
produce either:}

\fixit{%
yackity yack, yakity yack, yakity yack, paragraphs, I want to \textit{ensure their last line} is neither 
overly short nor overly long. To that end, I'm looking for settings that 
produce either:}

\fixit{%
yack, yackity yack, yakity yack, yakity yack, paragraphs, I want to \textit{ensure their last line} is neither 
overly short nor overly long. To that end, I'm looking for settings that 
produce either:}

\fixit{%
yackity yack, yackity yack, yakity yack, yakity yack, paragraphs, I want to \textit{ensure their last line} is neither 
overly short nor overly long. To that end, I'm looking for settings that 
produce either:}

\fixit{%
yack, yackity yack, yackity yack, yakity yack, yakity yack, paragraphs, I want to \textit{ensure their last line} is neither 
overly short nor overly long. To that end, I'm looking for settings that 
produce either:}

\fixit{%
yackity yack, yackity yack, yackity yack, yakity yack, yakity yack, paragraphs, I want to \textit{ensure their last line} is neither 
overly short nor overly long. To that end, I'm looking for settings that 
produce either:}

\fixit{%
yack, yackity yack, yackity yack, yackity yack, yakity yack, yakity yack, paragraphs, I want to \textit{ensure their last line} is neither 
overly short nor overly long. To that end, I'm looking for settings that 
produce either:}

\fixit{%
yackity yack, yackity yack, yackity yack, yackity yack, yakity yack, yakity yack, paragraphs, I want to \textit{ensure their last line} is neither 
overly short nor overly long. To that end, I'm looking for settings that 
produce either:}

\fixit{%
yack, yackity yack, yackity yack, yackity yack, yackity yack, yakity yack, yakity yack, paragraphs, I want to \textit{ensure their last line} is neither 
overly short nor overly long. To that end, I'm looking for settings that 
produce either:}

\fixit{%
yackity yack, yackity yack, yackity yack, yackity yack, yackity yack, yakity yack, yakity yack, paragraphs, I want to \textit{ensure their last line} is neither 
overly short nor overly long. To that end, I'm looking for settings that 
produce either:}

\fixit{%
yack, yackity yack, yackity yack, yackity yack, yackity yack, yackity yack, yakity yack, yakity yack, paragraphs, I want to \textit{ensure their last line} is neither 
overly short nor overly long. To that end, I'm looking for settings that 
produce either:}

\fixit{%
yackity yack, yackity yack, yackity yack, yackity yack, yackity yack, yackity yack, yakity yack, yakity yack, paragraphs, I want to \textit{ensure their last line} is neither 
overly short nor overly long. To that end, I'm looking for settings that 
produce either:}

\fixit{%
yack, yackity yack, yackity yack, yackity yack, yackity yack, yackity yack, yackity yack, yakity yack, yakity yack, paragraphs, I want to \textit{ensure their last line} is neither 
overly short nor overly long. To that end, I'm looking for settings that 
produce either:}

\fixit{%
yackity yack, yackity yack, yackity yack, yackity yack, yackity yack, yackity yack, yackity yack, yakity yack, yakity yack, paragraphs, I want to \textit{ensure their last line} is neither 
overly short nor overly long. To that end, I'm looking for settings that 
produce either:}

\end{document}

边距=1.5英寸

边距 = 1.7 英寸

边距 = 1.9 英寸

原始方法

但宏所做的是逐字逐句地复述段落，直到最后 4 个单词。然后，它确定需要超出的最后单词数，并将它们与.2\linewidth一起捆绑在中。如果最后 3 个单词不超过，则它会使用中的所有 4 个单词。\mbox\hspace{.2\linewidth}.2\linewidth\mbox

对于 OP 的要求，\sloppy几乎肯定会需要，因为我们正在讨论.4\linewidth一下子改变文本长度（这几乎总是不受欢迎的）。所以我添加了它。

有一件事会破坏这种方法，那就是如果之前打开的组在段落的最后 4 个字内结束。例如，当在段落\textit结尾附近关闭一个长句子时，就会出现这种情况。

另一件需要注意的事情是，一个完美的矩形段落将绝不可以用这种方法创建，因为\hspace在段落末尾添加了。

\documentclass{article}
\newcommand\fixit[1]{\fixithelp#1 \cr\relax}
\def\fixithelp#1 #2 #3 #4 #5\relax{\ifx \cr#5\finishup#1 #2 #3 #4\relax%
  \else#1 \fixithelp#2 #3 #4 #5\relax\fi}
\def\finishup#1 #2 #3 #4\relax{ %
  \setbox0=\hbox{#4}%
  \ifdim\wd0>.2\linewidth\relax #1 #2 #3 \mbox{#4\hspace{.2\linewidth}}\else%
    \setbox0=\hbox{#3 #4}%
    \ifdim\wd0>.2\linewidth\relax #1 #2 \mbox{#3 #4\hspace{.2\linewidth}}\else%
      \setbox0=\hbox{#2 #3 #4}%
      \ifdim\wd0>.2\linewidth\relax #1 \mbox{#2 #3 #4\hspace{.2\linewidth}}\else%
        \mbox{#1 #2 #3 #4\hspace{.2\linewidth}}%
      \fi%
    \fi%
  \fi%
}
\sloppy
\parskip1em
\begin{document}
\fixit{typesetting 
paragraphs, I want to \textit{ensure their last line} is neither 
overly short nor overly long. To that end, I'm looking for settings that 
produce either:}

\fixit{%
paragraphs, I want to \textit{ensure their last line} is neither 
overly short nor overly long. To that end, I'm looking for settings that 
produce either:}

\fixit{%
paragraphs, I want to \textit{ensure their last line} is neither 
overly short nor overly long. To that end, I'm looking for settings that 
produce overlylongwords:}

\fixit{%
I want to \textit{ensure their last line} is neither 
overly short nor overly long. To that end, I'm looking for settings that 
produce overlylongwords:}

\fixit{%
typesetting paragraphs, I want to \textit{ensure their last line} is neither 
overly short nor overly long. To that end, I'm looking for settings that 
produce I I I I:}

\fixit{%
typesetting I want to \textit{ensure their last line} is neither 
overly short nor overly long. To that end, I'm looking for settings that 
produce I I I I:}
\end{document}

Answer 1