[Tex/LaTex] Class options declaration error: Undefined control sequence

class-optionsdocumentclass-writing

I'm trying to write a class file with certain options (e.g centered title, vs title on the left). When I compile a *.tex file that calls this class, I get the an undefined control sequence error for \@centeredtrue:

! Undefined control sequence.
\ds@centered ->\@centeredtrue

Below is my MWE class file; I drew on how to declare options from the article.cls file. I don't understand why I'm getting this error, when the article.cls class file has similar option declarations for its oneside and twoside options, but the article.cls file doesn't throw this error.

\NeedsTeXFormat{LaTeX2e}
\ProvidesClass{mwe}[2014/02/18 v0.0.1 Example Class For Errors]

\DeclareOption{centered}{\@centeredtrue}
\DeclareOption{flank}{\@centeredfalse}
\ExecuteOptions{centered}
\ProcessOptions

\endinput

My intent is to run conditional code dictated by my class's option.

Best Answer

\NeedsTeXFormat{LaTeX2e}
\ProvidesClass{mwe}[2014/02/18 v0.0.1 Example Class For Errors]

\newif\if@centered  \@centeredfalse %%%%%%%%%%%%%%%%%%%%%  
\DeclareOption{centered}{\@centeredtrue}
\DeclareOption{flank}{\@centeredfalse}
\ExecuteOptions{centered}
\ProcessOptions

\endinput

Related Solutions

[Tex/LaTex] Changing the default options of a document class

You could declare a string option that accepts the font size and defaults to 11pt. However, this will come at the expense of the top class no longer being aware of what exactly it is doing. But that's a principal problem of upwards compatibility. E.g.

\NeedsTeXFormat{LaTeX2e}
\ProvidesClass{atop}[16/07/2011]

\RequirePackage{kvoptions}
% Declare a string option `fntsize' that is unique to the derived
% class `atop'. It will accept anything assuming `11pt' if
% unspecified.
\DeclareStringOption[11pt]{fntsize}
% probably more options...
\ProcessKeyvalOptions{atop}\relax
\PassOptionsToClass{\atop@fntsize}{article}

% Assume that any unknown option will be understood by the base class:
\DeclareOption*{%
  \PassOptionsToClass{\CurrentOption}{article}%
}
\ProcessOptions\relax

% Now load the base class with the `fntsize' option and any unknown
% option:
\LoadClass{article}

If you happen to be the author of the base class and hence have the freedom to make it "a good base class", you might do some fancier things. For example, you could add a macro that allows executing options after the class has been loaded. (Like hyperref's \hypersetup or geometry's \geometry.) Then you could further add a macro, say \getOptionList, that returns a comma separated list of all options. You may then retrieve the list of options accepted by the base class in the derived class and use it to make further decisions without hardcoding the status quo of base options.

Best

[Tex/LaTex] Best practice for setting package options through class options

You can use \geometry and options therein multiple times. So for this application I suggest something like

\DeclareOption{myopt}{%
  \AtEndOfPackage{\geometry{paperwidth=3cm,paperheight=9cm}}}

\ProcessOptions\relax
\RequirePackage{geometry}
\geometry{paperwidth=12cm,paperheight=12cm} % default

In more general cases it may be more difficult, because options are executed in the order they are listed in the package, when it calls \ProcessOptions.

So if packageB.sty declares x and nox in this order (later using \ProcessOptions, not \ProcessOptions*) and you say in packageA.sty

\DeclareOption{x}{\PassOptionsToPackage{x}{packageB}}
\DeclareOption{nox}{\PassOptionsToPackage{nox}{packageB}}

\ExecuteOptions{nox}
\ProcessOptions\relax
\RequirePackage{packageB}

then nox will be executed last by packageB no matter if you call packageA with the x option.

So a more precise answer depends on "real world" situations.

Best Answer

Related Solutions

[Tex/LaTex] Changing the default options of a document class

[Tex/LaTex] Best practice for setting package options through class options

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