How to change a whole row of a table

Each cell of a table is set in a box, so that a change of font style (or whatever) only lasts to the end of the cell. If one has a many-celled table, or a long one which needs lots of rows emphasising, putting a font style change command in every cell will be impossibly tedious.

With the array package, you can define column modifiers which will change the font style for a whole column. However, with a bit of subtlety, one can make such modifiers affect rows rather than columns. So, we set things up by:

\usepackage{array}
\newcolumntype{$}{>{\global\let\currentrowstyle\relax}}
\newcolumntype{^}{>{\currentrowstyle}}
\newcommand{\rowstyle}[1]{\gdef\currentrowstyle{#1}%
  #1\ignorespaces
}
Now, we put '$' before the first column specifier; and we put '^' before the modifiers of subsequent ones. We then use \rowstyle at the start of each row we want to modify:
\begin{tabular}{|$l|^l|^l|}   \hline
  \rowstyle{\bfseries}
  Heading & Big and & Bold \\ \hline
  Meek & mild & entry      \\
  Meek & mild & entry      \\
  \rowstyle{\itshape}
  Strange & and & italic   \\
  Meek & mild & entry      \\ \hline
\end{tabular}
The array package works with several other tabular-like environments from other packages (for example longtable), but unfortunately this trick won't always work.
array.sty
Distributed as part of macros/latex/required/tools (zip, browse)

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