Use alternadores no biblatex `printbibliography`

Question

Considere o seguinte:

\documentclass{article}
\usepackage[backend=bibtex8]{biblatex}
\begin{filecontents*}{bib.bib}
@mastersthesis{toto,
author={Toto},
title={My thesis},
year={2009},
school={Paris 129},
keywords={mem}
}
\end{filecontents*}
\addbibresource{bib.bib}
\newtoggle{display}
\toggletrue{display}
\begin{document}
\nocite{*}
\printbibliography[\iftoggle{display}{keyword=mem}{notkeyword=mem}]
\togglefalse{display}
\printbibliography[\iftoggle{display}{keyword=mem}{notkeyword=mem}]
\end{document}

O comportamento que eu esperaria é que dependendo do valor de toggle display, as entradas com a palavra-chave memfossem exibidas ou não.

No entanto, tudo que recebo são ! Package keyval Error: keyword=mem undefined.erros ! Package keyval Error: notkeyword=mem undefined..

Answer 1

Você precisa expandir o argumento opcional antes de \printbibliographyvê-lo:

\begin{filecontents*}{\jobname.bib}
@mastersthesis{toto,
author={Toto},
title={My thesis},
year={2009},
school={Paris 129},
keywords={mem}
}
@mastersthesis{toto2,
author={Toto},
title={My thesis not mem},
year={2009},
school={Paris 129},
keywords={notmem}
}
\end{filecontents*}

\documentclass{article}
\usepackage[backend=bibtex8]{biblatex}

\addbibresource{\jobname.bib}
\newtoggle{display}
\toggletrue{display}
\begin{document}
\nocite{*}

\begingroup\edef\x{\endgroup\noexpand
  \printbibliography[\iftoggle{display}{keyword=mem}{notkeyword=mem}]%
}\x

\togglefalse{display}

\begingroup\edef\x{\endgroup\noexpand
  \printbibliography[\iftoggle{display}{keyword=mem}{notkeyword=mem}]%
}\x

\end{document}

Uma interface mais amigável pode ser obtida comxparse

\begin{filecontents*}{\jobname.bib}
@mastersthesis{toto,
author={Toto},
title={My thesis},
year={2009},
school={Paris 129},
keywords={mem}
}
@mastersthesis{toto2,
author={Toto},
title={My thesis not mem},
year={2009},
school={Paris 129},
keywords={notmem}
}
\end{filecontents*}

\documentclass{article}
\usepackage[backend=bibtex8]{biblatex}
\usepackage{xparse}

\addbibresource{\jobname.bib}
\newtoggle{display}
\toggletrue{display}

\ExplSyntaxOn
\NewDocumentCommand{\xprintbibliography}{o}
 {
  \IfNoValueTF{#1}
   {
    \printbibliography
   }
   {
    \clement_xprintbibliography:x { #1 }
   }
 }
\cs_new_protected:Npn \clement_xprintbibliography:n #1
 {
  \printbibliography[#1]
 }
\cs_generate_variant:Nn \clement_xprintbibliography:n { x }
\ExplSyntaxOff

\begin{document}
\nocite{*}

\xprintbibliography[\iftoggle{display}{keyword=mem}{notkeyword=mem}]%

\togglefalse{display}

\xprintbibliography[\iftoggle{display}{keyword=mem}{notkeyword=mem}]%

\end{document}

Answer 2

Por um motivo que ainda não entendi, não há problema em deixar keyword/ notkeyworddepender do botão de alternância.

Para facilitar a leitura, incluí o \iftoggle{display}{keyword}{notkeyword}como um novo comando ( etiquette, que significa "rótulo" em francês), mas isso não é obrigatório.

\documentclass{article}
\usepackage[backend=bibtex8, defernumbers=true]{biblatex}
\begin{filecontents*}{bib.bib}
@mastersthesis{toto1,
author={Toto},
title={My thesis},
year={2009},
school={Paris 129},
keywords={mem}
}
@mastersthesis{toto2,
author={Toto},
title={My new thesis},
year={2015},
school={Paris 32},
}
\end{filecontents*}
\addbibresource{bib.bib}
\newtoggle{display}
\toggletrue{display}

\newcommand{\etiquette}{\iftoggle{display}{keyword}{notkeyword}}

\begin{document}
\nocite{*}
\printbibliography[\etiquette=mem, title={With mem keyword}]
\togglefalse{display}
\printbibliography[\etiquette=mem, title={With\emph{out} mem keyword}]
\end{document}

Compila sem aviso prévio e fornece o esperado:

---

Surpreendentemente, o contrário, ou seja

\newcommand{\etiquette}{\iftoggle{display}{mem}{bubu}}
...
\printbibliography[notkeyword=\etiquette, title={Without mem keyword}]
\togglefalse{display}
\printbibliography[notkeyword=\etiquette, title={Without bubu keyword}]
...

não funciona (sem aviso, mas tudo é citado sempre).