added \ekdpb for conditional page breaks

1 files changed, 44 insertions, 0 deletions

diff --git a/ekdosis.dtx b/ekdosis.dtx
index c7176e7..6e975d8 100644
--- a/ekdosis.dtx
+++ b/ekdosis.dtx
@@ -4220,6 +4220,20 @@ subtype="arabtex">'inna 'abI kAna mina
 % edition text is ready for any substantial change in the preceding
 % pages may result in pages that break just after they begin.
 %
+% \paragraph{Conditional page breaks}
+% \DescribeMacro{\ekdpb} \cs{ekdpb}\oarg{page no}\marg{line no}
+% \newfeature[v1.2]\\
+% One way to avoid this inconvenience is to use \cs{ekdpb} instead of
+% the standard \cs{pabebreak} command provided by \LaTeX\ to insert
+% conditional page breaks. \cs{ekdpb} takes as mandatory argument an
+% integer that represents the line number where the page break should
+% take place. An optional argument allows to further specify the page
+% number where the page break should occur. The value that is expected
+% is the page number as it is printed\===e.g.\ an Arabic, Roman or
+% alphanumeric number. If the specified conditions are not met, then
+% the page break is not triggered.
+%
+% \paragraph{Using \texttt{maxentries}}
 % Another way\---should the edition text fall into the vicious circle
 % too often\---is to limit the number of entries per page that a given
 % layer of apparatus criticus may accept as described above
@@ -6431,6 +6445,7 @@ Sample text with a \textcolor{red}{word} in red.
 }
 \@onlypreamble\DeclareApparatus
 %    \end{macrocode}
+% \end{macro}
 % \begin{macro}{\addentries}
 % \changes{v1.1}{2020/11/04}{modifies the number of accepted entries
 % on the current page.}
@@ -6448,6 +6463,35 @@ Sample text with a \textcolor{red}{word} in red.
 }
 %    \end{macrocode}
 % \end{macro}
+% \begin{macro}{\ekdpb}
+% \changes{v1.2}{2021/02/21}{insert conditional page breaks}
+% \cs{ekdpk}\oarg{page no}\marg{line no} is used to insert conditional
+% page breaks by specifying that the page break should occur only on a
+% given line and optionally a given page. If the specified conditions
+% are met then this command triggers \cs{pagebreak}.
+%    \begin{macrocode}
+\NewDocumentCommand{\ekdpb}{o m}{%
+  \def\@tmpoarg{#1}%
+  \def\@tmpmarg{#2}%
+  \luadirect{ekdosis.dolnlab(\luastringN{#2})}%
+  \linelabel{\luadirect{tex.sprint(ekdosis.getlnlab())}}%
+  \def\tmpln{%
+    \getrefnumber{\luadirect{tex.sprint(ekdosis.getlnlab())}}}%
+  \def\tmppg{%
+    \getpagerefnumber{\luadirect{tex.sprint(ekdosis.getlnlab())}}}%
+  \IfNoValueTF{#1}
+  {\ifnum\@tmpmarg=\tmpln
+    \pagebreak
+    \fi}
+  {\ifnum
+    \pdf@strcmp{\@tmpoarg}{\tmppg} = 0
+    \ifnum\@tmpmarg=\tmpln
+    \pagebreak
+    \fi
+    \fi
+  }\ignorespaces
+}
+%    \end{macrocode}
 % \end{macro}
 % Apparatus-related settings and functions. Some booleans to check if
 % an apparatus should be inserted and what is the current environment.