Macros – Resolving Package Incompatibilities: etoolbox, hyperref, and bm, standalone

etoolboxhyperrefincompatibilitymacrosstandalone

I am trying to transition to using the etoolbox package, but seem to have run into some difficulties and they appear related to the hyperref and bm packages which to me seem totally unrelated. The MWE example compiles since \RemoveEToolbox is defined and shows that there is no apparent problem before etoolbox was used.

Commenting out the \def\RemoveEToolbox{} line produces two problems:

With both the \renewcommand, and the usepackage{hyperref} commented, this results in "Runaway argument? Paragraph ended before \bm@test@token was complete".
Including the usepackage{hyperref} (with \renewcommand commented) results in "Undefined control sequence. \Call@AtVeryEndDocument …cumentHook \@undefined"

But if uncomment the \renewcommand{\bm}{#1} line (effectively doing without any \bm), then this seems to compile.

I have been using this for a while now and things appeared to have been working fine, but now that I attempt to use etoolbox I seem to run into problems.

\documentclass{standalone}
\def\RemoveEToolbox{}% Shows that this works fine without {etoolbox}

\usepackage{amsmath}
\usepackage{xcolor}
\usepackage{bm}

\ifdefined\RemoveEToolbox
    \newcommand*{\iftoggle}[3]{#2}% Default to true value of "if"
\else
    \usepackage{etoolbox}
    \newtoggle{paper}
    \toggletrue{paper}

    %\renewcommand{\bm}[1]{#1}% Why can't I have a normal \bm with {etoolbox}?
\fi

% \usepackage{hyperref}

\begin{document}

This document is intended for 
\iftoggle{paper}{paper}{electronic}
distribution.

\bm{\textcolor{blue}{Solve $x^2-1=0$}}

\begin{align*}
    a &= b\\
    \iftoggle{paper}{
        c &= d\\
    }{}
    e &= f\\
\end{align*}
\end{document}

Best Answer

The issues is that both the standalone class and the etoolbox package redefine the document environment. This causes a clash. You can avoid this by loading etoolbox before the class using \RequirePackage. I will try to support the normal of this package, but it will take a while until I have to time to release a new version of standalone.

Workaround:

\def\RemoveEToolbox{}% Shows that this works fine without {etoolbox}

\ifdefined\RemoveEToolbox
    \newcommand*{\iftoggle}[3]{#2}% Default to true value of "if"
\else
    \RequirePackage{etoolbox}
    \newtoggle{paper}
    \toggletrue{paper}

    %\renewcommand{\bm}[1]{#1}% Why can't I have a normal \bm with {etoolbox}?
\fi

\documentclass{standalone}

\usepackage{amsmath}
\usepackage{xcolor}
\usepackage{bm}

% \usepackage{hyperref}

\begin{document}

This document is intended for 
\iftoggle{paper}{paper}{electronic}
distribution.

\bm{\textcolor{blue}{Solve $x^2-1=0$}}

\begin{align*}
    a &= b\\
    \iftoggle{paper}{
        c &= d\\
    }{}
    e &= f\\
\end{align*}
\end{document}

Update 2011/12/21

The new version 1.0 of standalone works fine with etoolbox, due to a changed way to patch the document environment. However, the new default settings ignore paragraph breaks, so you will a problem with align*. You can fix easily this by using the varwidth class option.

Related Solutions

Hyperref – Fixing Vertical Position Issue After Navigating to Hypertargets from Hyperlinks in PDFs

The baseline is well known in TeX, but not the height of the current line. Only TeX knows this at a later time, after paragraph breaking. Measuring the height via boxing looses line breaking. \vadjust pre of pdfTeX was (is?) not stable enough, some circumstances causes segmentation faults. To some degree LuaTeX's attributes might help at the cost of a complete different non-trivial implementation. Back to the question, the current workaround is already mentioned (e.g. \Hy@raisedlink with empty \hypertarget).

Etoolbox – Difference Between \newbool and \newtoggle in Etoolbox Package

\newbool{mybool} is almost the same as \newif, but it checks whether \ifmybool is already defined, which LaTeX doesn't:

\newrobustcmd*{\newbool}[1]{%
  \expandafter\@ifdefinable\csname if#1\endcsname{%
    \expandafter\newif\csname if#1\endcsname}}

There's also \providebool which does nothing if the conditional is already defined.

Similarly, \ifbool is a wrapper around the usual construction

\if...
  \expandafter\@firstoftwo
\else
  \expandafter\@secondoftwo
\fi

with a preliminary check whether the conditional is defined. So it can be used also for primitive conditionals:

\ifbool{hmode}{<something for horizontal mode>}{<something else>}

Instead \newtoggle{mytoggle} is defined by

\newrobustcmd*{\newtoggle}[1]{%
  \ifcsdef{etb@tgl@#1}
    {\etb@error{Toggle '#1' already defined}\@eha}
    {\cslet{etb@tgl@#1}\@secondoftwo}}

so it checks whether the toggle is already defined and, if not, it sets it to "false". The constructed macro \etb@tgl@mytoggle is either \@firstoftwo (corresponding to "true") or \@secondoftwo (corresponding to "false"). When one says

\iftoggle{mytoggle}{<true>}{<false>}

etoolbox simply checks whether the toggle is defined and, if it is, just puts \etb@tgl@mytoggle in the input stream, thus doing "the right thing", because it chooses either <true> or <false> depending if it is \@firstoftwo or \@secondoftwo.

Note that \toggletrue is defined as

\newrobustcmd*{\toggletrue}[1]{%
  \ifcsdef{etb@tgl@#1}
    {\cslet{etb@tgl@#1}\etb@toggletrue}
    {\etb@noglobal\etb@err@notoggle{#1}}}

so it can be preceded by \global: indeed \ifcsdef is expandable, so if the toggle foo is not defined, after \global\toggletrue{foo} we'd remain with

\global\etb@noglobal\etb@err@notoggle{#1}}

which becomes

\global\let\relax\relax\etb@err@notoggle{#1}

that effectively removes the \global by doing a harmless \let (almost harmless, because it can impact on the stack memory, but since there's an error raised anyway, the user will correct it). If instead the toggle \foo is defined, we remain with

\global\cslet{etb@tgl@foo}\etb@toggletrue

so, again,

\global\expandafter\let\csname etb@tgl@foo\endcsname\etb@toggletrue

where \etb@toggletrue is the same as \@firstoftwo. The same holds, of course, for \togglefalse.

Which one to prefer? If you plan to use also the traditional \if... syntax, then \newbool is needed. Otherwise it's just a matter of personal preference.

Both booleans and toggles can be used in boolean expression (\ifboolexpr), so there's no difference for that usage either. Note that \global\booltrue and \global\boolfalse are legal too.