Key Value option in package

Question

I trying to write a package, and I'd like to specify whether there should be colour or not.
I'd like to do:

\usepackage[color=false]{foo}

and have this set

\RequirePackage[color=false]{hyperref}

or true as the case may be. What's the best way to do this?

Answer 1

If you want all the options to your package to be passed to hyperref then you can just do

\DeclareOption*{\PassOptionsToPackage{\CurrentOption}{hyperref}
\ProcessOptions\relax
\RequirePackage{hyperref}

see clsguide.tex documentation in the LaTeX base.

I just read clsguide:-) and if this is all you want to do, it points out that there is a more efficient shortcut to all the above three lines

\RequirePackageWithOptions{hyperref}

Answer 2

Another option is to use keyreader

\begin{filecontents}{mypack.sty}
\ProvidesPackage{mypack}

\usepackage{keyreader}

% Define the keys in family MYFAM and set the
% macor prefix to my@
\krddefinekeys{MYFAM}[my@]{
    % define a command key 'say' that sores
    % it’s value in \my@say
    cmd/say/jump/;
    % [1] define a boolean 
    bool/colori/true/;
    % [2] define a boolean and store the value
    bool/colorii/true/\def\my@colorii{#1};
}
% booleand are not preset by defualt so we
% do it manually
\krdsetkeys{MYFAM}{colori=false,colorii=false}

% Process the package options
\krdProcessOptions<MYFAM>\relax

% with version [1]
%\ifmy@colori
%   \RequirePackage[colorlinks=true]{hyperref}
%\else
%   \RequirePackage[colorlinks=false]{hyperref}
%\fi

% with version [2]
\RequirePackage[colorlinks=\my@colorii]{hyperref}

\newcommand{\mycmd}[1]{%
    % use the value of 'say'
    #1 says \my@say.
}
\end{filecontents}

\documentclass{article}

\usepackage[%
    say={sit down},
    colori=true,% [1]
    colorii=false,% [2]
]{mypack}

\begin{document}
\mycmd{Simon}

\url{www.myurl.com}
\end{document}

Notes

• hyperref has no color option (at least my version hasn’t)

• Version [1] is the shorter was if you want to access only one hyperref key

• Version [2] is better if you want to access more then one option.

  • For that we store the value of the option an pass it to hyperref later. Booleans don’t store their value by default, they only create new \if…

  • Why not use a cmd for this version? Because bool key checks if it’t value matches true or false

---

Maybe it’s better to use the pdf key processing since it’s more related with the beamer class, but I’m not familiar with that.

Answer 3

Another option is to use kvoptions and etoolbox, in your .sty file, write:

...
\RequirePackage{kvoptions}
\RequirePackage{etoolbox}

%% if the variable 'color' is
%% 1. not included                  : it will be set to 'false'
%% 2. included but not given a value: it will be set to 'true'
%% 3. included and given a value    : it will be set to the value that is given
\DeclareStringOption[false]{color}[true]

\newif \ifcolor %% new Boolean variable is default to 'false'
\ifdefstring{\foo@color}{true}{\colortrue}{} %% set the Boolean variable to 'true' if '\foo@color' is 'true'

\ifcolor
\RequirePackage[color = true]{hyperref}
\else
\RequirePackage[color = false]{hyperref}
\fi
...

Then in your document you can specify the option 'color' with:

...
\usepackage[color]{foo}         %% color = true
\usepackage[color = true]{foo}  %% color = true
\usepackage[color = false]{foo} %% color = false
...