[Tex/LaTex] Pretty printing of LaTeX code

sourcecode

In many MWE here on TeX.SE the LaTeX code is written without explanatory comments and as compact as possible. An Example:

\documentclass[ngerman,fontsize=12pt,pagesize]{scrreprt}
\usepackage{lmodern} 
\usepackage[T1]{fontenc} 
\usepackage[latin9]{inputenc} 
\usepackage[backref=page,breaklinks,colorlinks]{hyperref}
\hypersetup{pdftitle={Titel},pdfauthor={username}}
\begin{document}
Blindtext. \url{http://tex.stackexchange.com}.
\end{document}

This is particularly difficult to read for LaTeX beginners and to understand. So I got used a certain style of writing MWEs. I use a space (to be changed to a % character if neccessary) in front of macros like \usepackage{} or I write each option for a document class or a package in a seperate line with a leading coma. So I'm able to comment the meaning of the option. And one can see which lines are commented. Added now to the example: You can easy switch between two fonts or two encriptions. The same example pretty printed:

\documentclass[%
  ngerman
%,paper=a4           % Papiergröße (Voreinstellung)
 ,fontsize=12pt      % Brotschrift-Grad
%,parskip=full       % Abstand Absätze, erste Zeile nicht eingezogen.
 ,pagesize           % entscheidet zur Laufzeit, ob dvips oder pdf
]{scrreprt}

 \usepackage{lmodern}          % Latin Modern
%\usepackage{libertine}        % Libertine Legacy
 \usepackage[T1]{fontenc}      % Ausgabezeichensatz
 \usepackage[latin9]{inputenc} % Windows PC
%\usepackage[utf8]{inputenc}   % Unicode
 \usepackage[%
   backref=page                % Verweis auf Seite
% ,pagebackref                 % wie zuvor
  ,breaklinks                  % Links überleben einen Zeilenumbruch 
  ,colorlinks                  % Links farbig für PDF-Betrachtung 
 ]{hyperref}

\hypersetup{%          % Konfiguration hyperref
  pdftitle={Titel}     % Titel
 ,pdfauthor={username} % Verfasser
%,linktoc=all          % Alles als Link setzen
} 

\begin{document}
Blindtext. \url{http://tex.stackexchange.com}.
\end{document}

Question:
Are there any objections to format a LaTeX code like this?
For example,

  • can the leading space of macro \usepackage{} lead to errors,

  • can the notation ,option = value lead to errors (I prefer this kind of notation to get rid of missing commas. If all commas are in the same column, it is much harder to forget one (the first line must not have a leading comma)).

Best Answer

Under normal circumstances (i.e. not in verbatim or similar), TeX converts line ends to spaces and combines multiple spaces into a single space. It also skips spaces at the start of a line. Thus

% Comment to show start of text
\usepackage{foo}

and

% Comment to show start of text
   \usepackage{foo}% Note spaces

are equivalent. In the same way

\hypersetup{%      % Konfiguration hyperref
  pdftitle={Titel} % Titel
 ,pdfauthor={username} % Verfasser

is equivalent to

\hypersetup{pdftitle={Titel} ,pdfauthor={username} ...

(note the space before the comma). Most LaTeX keyval implementations ignore spaces 'before' and 'after' each entry, so

\setkeys{somepkg}{foo=bar,foo2=bar2}

and

\setkeys{somepkg}{  foo=bar  ,  foo2=bar2  }

are equivalent, meaning that the space in the hyperref line is also fine. It's worth noting that most LaTeX keyval implementations also ignore spaces around the =, so that

foo = bar

and

foo=bar

are equivalent. (This is not true for ConTeXt. It's also worth noting that datatool uses a keyval implementation which is much less forgiving on spaces.)

Not directly related, but many people prefer having the commas at the end of the line

\hypersetup{%      % Konfiguration hyperref
  pdftitle={Titel}, % Titel
  pdfauthor={username}, % Verfasser
% linktoc=all      % Alles als Link setzen
}

which follows exactly the same rules: you can have the commas 'flush' or aligned and spaces will still be ignored.

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