Add \_Von to bibmark when \nonumcitations is set

[pabloabur]

Hi,

Is there a recommended way of adding von/van/da/etc before lastnames in the output of \cite?

I tried changing \_authorname (to get _Lastname and _Von only) and \_createbibmark but I am not sure whether there are bad side effects from this. Also, there is a space before the first author name that I cannot get rid of. In the example below, the output looks like this:

Citation [ Lastname1, Lastname2 and van Lastname3, 2024].
          ^

I tried to create a temporary variable inside \_createbibmark but that leads to an error. I was thinking that I could do something like \def\temp{#3}\ifx\temp\empty\else#3\fi #2, but that does not work for some reason. Has anybody done this before?

MWE
test.tex:

\fontfam[LMfonts]

\nonumcitations
\bibtexhook{
    \def\_createbibmark #1;#2,#3;#4,#5;#6,#7;#8,#9\_fin{%
        \ifx ^#8^%
            \ifx ^#6^%
                \ifx ^#4^%
                    #3 #2,
                \else
                    #3 #2 and #5 #4,
                \fi
            \else #3 #2, #5 #4 and #7 #6,
            \fi
        \else #3 #2 et al.,
        \fi
        \space #1% 
    }
    \_def\_authorname{%
        \_ifx\_authlist\_undefined \_edef\_authlist{\_Lastname,\_Von}%
            \_else \_edef\_authlist{\_authlist;\_Lastname,\_Von}\_fi
            \_ifnum\_NameCount>0\_namecount\_relax\_else \_commonname \_fi
            \_ifnum\_NameCount=0\_namecount\_relax \_maybeetal \_fi
    }

}

Citation \cite[ref].

\bigskip
\usebib/s (iso690) bibsample
\bye

biblist.bib:

@ARTICLE{ref,
    title="title",
    author="Lastname1, Firtname1 and Lastname2, Firstname2 and van Lastname3, Firtname3",
    year="2024"
    }

[olsak]

The \_createbibmark macro must be expandable because its output is expanded to the .ref file (you can look into this file). If you want to have \def here, you have to prefixed it by \immediateassignment. But it isn't best idea. I will try something else and post it here yesterday. The space before Lastname1 is due to #3 #2 where #3 is empty "von" and #2 is Lastname1. The space between #3 #2 is this problematic space. I will try to suggest a slightly different solution. The question: do you want to print maximal 3 authors in your \cite or possibly more?

[pabloabur]

Thank you, I appreciate it. Yes, I would like 3 to be the maximum. More than that should become Lastname1 et al. (year).

[olsak]

You can re-define \_authorname if you plan to use only bib-iso690, because the \_authorname macro in bib-simple is defined differently. Then, you can use following macros:

\fontfam[LMfonts]

\nonumcitations
\bibtexhook{
    \def\_createbibmark #1;#2,#3;#4,#5;#6,#7;#8,#9\_fin{%
       \ifx ^#4^% single author
          \printvon{#3}#2,
       \else \ifx ^#6^% two authors
          \printvon{#3}#2 and \printvon{#5}#4,
       \else \ifx ^#8^% three authors
          \printvon{#3}#2, \printvon{#5}#4 and \printvon{#7}#6,
       \else          % more authors
          \printvon{#3}#2, \printvon{#5}#4, \printvon{#6}#7 et al.,
       \fi\fi\fi
    #1% year
    }
    \def\printvon#1{\ifx^#1^\else #1 \fi} % print von + space

    \_def\_authorname{%
        \_ifx\_authlist\_undefined \_edef\_authlist{\_Lastname,\_Von}%
            \_else \_edef\_authlist{\_authlist;\_Lastname,\_Von}\_fi
            \_ifnum\_NameCount>0\_namecount\_relax\_else \_commonname \_fi
            \_ifnum\_NameCount=0\_namecount\_relax \_maybeetal \_fi
    }

}

Citation \cite[ref].

\bigskip
\usebib/s (iso690) bibsample
\bye

Second variant is to keep \_authorname and \_authlist without changes and define only \_createbibmark. This definition is more tricky:

\fontfam[LMfonts]

\nonumcitations
\bibtexhook{
%    \def\_createbibmark #1;#2\_fin{\createbibmarkA #2\_fin #1} % from previous experiments
    \def\_createbibmark #1;#2,#3,#4,#5;#6,#7;#8,#9\_fin{%
       \printvon{#4}#2%
       \ifx^#6^, % single name
       \else
          \ifx^#8^ and \createbibmarkB #6,#7;,   % two names
          \else    , \createbibmarkB #6,#7;%
                     \createbibmarkC #8,#9\_fin  % three or more names  
          \fi
       \fi
       #1% year
    }
    \def\createbibmarkB #1,#2,#3,#4;{\printvon{#3}#1}
    \def\createbibmarkC #1,#2,#3,#4;#5,#6\_fin {%
       \ifx ^#5^ and \printvon{#3}#1,        % three names
       \else     ,   \printvon{#3}#1 et al., % more names
       \fi
    }
    \def\printvon#1{\ifx^#1^\else #1 \fi} % print von + space
}

Citation \cite[ref].

\bigskip
\usebib/s (iso690) bibsample
\bye

[pabloabur]

Thanks, both of these solutions work for me.

Could you please briefly explain \def\_createbibmark #1;#2\_fin{\createbibmarkA #2\_fin #1} though? As far as I understand, \_fin is like a placeholder for other arguments, so you can process more than 9 arguments, right? But I don't really get this line, especially since \createbibmarkA is not defined anywhere

[olsak]

Oops, I forgot to delete the line \def\_createbibmark #1;#2\_fin{\createbibmarkA #2\_fin #1} from my code. It was here from my previous experiments. The \_createbibmark is re-defined immediately at the next line. My previous experiment included \_def\createbibmarkA #1,#2;#3,#4;#5,#6;#7,#8\_fin{...} which prints first author #1,#2 and maybe second author #3,#4 (if not empty) etc. The #8 includes the data left after reading the first three authors finalized by \_fin. The "year" (#1 in \_createbibmark) is printed after the \createbibmarkA is finished.

[pabloabur]

Great, I think I get it now.