French typography recommendations

Question

This question led to a new package:
impnattypo

The French government publications office (Imprimerie Nationale) publishes a list of recommendations for French typography. I'm wondering how to implement some of these in LaTeX. I might actually come up with more later as I continue reading this booklet.

End of chapters/parts

In addition to the recommendations of removing footers on the last page of chapters/parts, it is recommended that these pages do not have less than 6 lines. I am guessing (it is not written) that if there are less than 6 lines, it is recommended to increase that number by forcing a page break in (one of) the previous page.

Hyphenation rules

• No odd page should finish with an hyphenated word;
• No more than 3 lines with hyphenated words should follow one another.

Answer 1

No odd page should finish with an hyphenated word;

\brokenpenalty=10000 will forbid any page (neither recto nor verso) from ending with a hyphen.

No more than 3 lines with hyphenated words should follow one another.

\doublehyphendemerits=1000000000 will strongly discourage two hyphenations in a row.

Answer 2

I'll give my non answer too.

It's in principle possible to have at least six lines in the final page of a chapter provided that the last paragraph is at least six lines long. Define

\newcommand{\closechapter}{%
  \begingroup\widowpenalties 6 10000 10000 10000 10000 10000 0 
  \par\endgroup
  % other customizations for the final page
}

and write \closechapter immediately after the final chapter's period (requires e-TeX extensions that should be present in any recent TeX distribution). If the last paragraph is less than five lines long, one can write \unskip\newline\indent\ignorespaces instead of the blank line between the final two paragraphs.

However, as already pointed out, such an "automatic" check will probably destroy the spacing in the preceding page, with a high risk of an Underfull \vbox.

No automatic procedure can replace human eye and judgment. Ensuring at least six lines in the last page of a chapter needs human intervention that no machine can possibly do, because machines don't understand English, French, Italian, or the language the document is written in.

The possibilities are so many: what if the chapter ends with two lines after an enumerated list? What if there's a quotation or a displayed formula? How do we count lines?

I don't believe in strict rules such as those by the Imprimerie Nationale; while I do agree that a final chapter page two lines long should be avoided, I could be satisfied with five. And I could accept a final hyphen in an odd page if all alternatives are worse (there usually are better alternatives, though).

Answer 3

Maybe not really answer your questions.

it is recommended that these pages do not have less than 6 lines.

I think this is much similar to the issues of widows and/or orphans. As far as I can tell there is no reliable and general way to do this in TeX. The better way is still to rely on a good editor (I mean a human editor, not a text editor or whatever).

I don't suggest to force a page break in a previous page. That will definitely make the documents look worse. Underfull vbox is very easy to be spotted by eyes and should be avoided as much as possible. It does much more harm than a few points of underfull or overfull hbox.

Hyphenation rules.

This can be partially addressed by microtypography, namely protrusion, expansion, and sometimes tracking.

When using pdftex, launch the microtype package. Its document is quite comprehensive and also contains a brief but good introduction to microtypography.

When using luatex, though microtype has support for it since luatex 0.4, support for opentype fonts loaded with luaotfload/fontspec is still in a upcoming version the last time I check. But you can use

\pdfprotrudechars2
\pdfadjustspacing2

to turn on these features. And with the protrusion and expansion features to setup the factors. With fontspec, use RawFeature = {protrusion = ...}, or define a new font feature or other methods. See documents of luaotfload for these two features. See fontspec documents for setting features.

With microtypography, the hyphenation is largely improved, and you will see much less hyphenation. Therefore much less chance you get three successive lines with hyphenations or a last in odd page with hyphenated work.

However this just reduces the chance of such things happening (dramatically), not prevent anyway. But if there are still such hyphenations left, they should be very few and can be addressed by an editor.