breqn

588 \eq@dump@box\unhbox\EQ@box
589 \@@par
590 }
25 Special processing for end-of-equation
At the end of a displayed equation environment we need to peek ahead for two
things: following punction such as period or command that should be pulled in
for inclusion at the end of the equation; and possibly also an \end{proof} with
an implied “qed” symbol that is traditionally included at the end of the display
rather than typeset on a separate line. We could require that the users type
\qed explicitly at the end of the display when they want to have the display take
notice of it. But the reason for doing that would only be to save work for the
programmer; the most natural document markup would allow an inline equation
and a displayed equation at the end of a proof to differ only in the environment
name:
... \begin{math} ... \end{math}.
\end{proof}
versus
...
\begin{dmath}
...
\end{dmath}.
\end{proof}
. The technical difficulties involved in supporting this markup within L ATEX 2e
are, admittedly, nontrivial. Nonetheless, let’s see how far we can go.
The variations that we will support are only the most straightforward ones:
\end{dmath}.
\end{proof}
or
\end{dmath}.
Perhaps a comment
\end{proof}
. If there is anything more complicated than a space after the period we will not
attempt to scan any further for a possible \end{proof}. This includes material
such as:
\begin{figure}...\end{figure}%
\footnote{...}
\renewcommand{\foo}{...}
\par
40