How to make LaTeX do auto punctuation like Word

Question

Something is bothering me while I use LaTeX. If using, for example, Word, it will automatically capitalize the first letter of the beginning of each sentence and also suggesting to make some other punctuation etc.

At this point, is there any tool or package available for this matter for LaTeX?

Answer 1

This is a misunderstanding: LaTeX doesn't help you to write your text, which is the job of the editor. I'm quite confident that such a thing (capitalize each first letter after a dot) can be achieved with emacs or vim.

Word is all and everything in one: editor, typesetting machine, spreadsheet and so on and does nothing really well (OK, millions of people disagree).

As an alternative solution you could use Word as the editor:

Save your file as .txt and use latexmk to compile it in the background. Disclaimer: Did not try this myself; it is a really strange idea.

Answer 2

Not a solution, but a longer comment:

For some people, automatic capitalization of some word processors is a "bug", not a "feature". As pointed Gonzalo Medina. The reason is that in practice there are many exceptions, and supervise/correct every automatic decision is very distracting. In my case, overall I hate write correctly abbreviated name species (e.g., H. sapiens, etc.) and realize that the stupid computer wrote H. Sapiens (of course, only after print the "final" version in paper of high quality). This seem of little importance, but look like that the author unknown the basic rules of binomial nomenclature of the species. In high level scientific journals your article could be rejected only for this mistake.

On the other hand, as Ryan pointed, this a issue only related with the editor. Tex engines are WYWIWIP programs (What You Wrote Is What I Print) not WYMIWIR (What you Mean is What I Render). Then main purpose of a LaTeX compiler as pdflatex is not make source code, but read it in plain text (made with any other program). Thus, some source code (your preamble, or you custom class or package) must say what do do.

Think twice about left this job to LaTeX. In the editor side, the question is only if this justify a bloatware. With LaTeX, just think in the dot character. Make . an active character as & is not an option, since you have the same symbol for end of sentences (full stops), end of the paragraphs (not followed by spaces + some character), abbreviations within upper cases (J. Smith) or not (No. 3), decimals (3.14), ellipsis, ... Testing every case? Good luck with this adventure. Even is possible with LaTeX 3 or whatever, I only expect a massively overloaded, fragile and incompatible code.

Then, the natural LaTeX option, at least for a user without a deep understanding of the guts of TeX (i.e., me) would be replace the period at the end of the sentence by some odd macro like \¶ to act like a full stop that replace the next character after the space, whithout touching periods of abbreviations, end of paragraphs, etc. A simple approach:

\documentclass{minimal}
\def\¶{. \MakeUppercase}
\begin{document}
This is a test\¶ this is a test.
\end{document}

This MWE produce:

This is a test. This is a test.

Using newunicodechar package you can even convert \¶ in only ¶ or some other non ASCII character:

\documentclass{minimal}
\usepackage[utf8]{inputenc}
\usepackage{newunicodechar}
\newunicodechar{¶}{. \MakeUppercase}
\begin{document}
This is a test¶ this is a test.
\end{document}

But is not so simple. Try simple constructions as ¶{\em this} or ¶\emph{this} in this MWE.

Anyway, the main drawback is no that, but the sacrifice of readability and easy writing because a little fix that is easily done by hand.

Answer 3

Actually you can capitalize the beginning of a new sentence by making . active and redfine it to first test if a space is following the period and then executing \ucmacro (a macro version of the \uppercase primitive) when a space was found and to print whatever was found when it wasn't a space:

\documentclass{article}

\begin{document}
\let\period=.
\catcode`\.=13%\active
\catcode`\@=11%letter
\def.{\period\afterassignment\@period\let\next= }
\def\@period{%
  \if\noexpand\next\@sptoken
    \next\expandafter\ucmacro
  \else
    \expandafter\next
  \fi
}
\def\ucmacro#1{\uppercase{#1}}
\catcode`\@=12%other

zzzzzzzz. capitalize this.but not this.
\end{document}

_{With honorable mentions to @egreg's answer on \let\foo\bar vs \let\foo=\bar}