Is it possible to create a new command by \newcommand or \def "inside" the .bib-file?
I am using LuaLaTeX and biblatex and organize my bibliography with BibDesk on a mac. I also store information about reprints of paper x in collection y. I add this information in the Addendum-field of biblatex by something like
\bibstring{reprintin}\intitlepunct\addspace\citeauthor{author:1986}\labelnamepunct\addspace\citetitle{author:1986}\addcomma\space\citeyear{author:1986}
etc.
For that I had to define some bibstrings in the preamble fo the .tex-files:
\NewBibliographyString{reprintin}
\DefineBibliographyStrings{american}{
reprintin = {Reprint in},
}
\DefineBibliographyStrings{british}{
reprintin = {Reprint in},
}
\DefineBibliographyStrings{german}{
reprintin = {Nachdruck in},
}
\DefineBibliographyStrings{ngerman}{
reprintin = {Nachdruck in},
}
I now would like to create a newcommand \bibreprintin that allows me to just prompt in the addendum-field \bibreprintin{author:1986} instead of entering the above code bibstring{reprintin} ....
Thereby I'd enable myself to change the look of the reprint-information later with "one click" should it become necessary later, and also make it safe that all reprint information for all publications in my bibliorgaphy look the same.
My question now is, if there is any possibility to use commands like \def, \newcommand, and \NewBibliographyString inside the .bib-file (for this is only one file) and not just inside every single .tex-file (for these are many different files I am working on).

addendum = {Reprint in \cite{<bibkey>}},. Note that what this requires is an extended cycle (latex, bibtex/biber, latex, bibtex/biber, latex) since thecitecommand won't be 'noticed' until the secondlatexrun. – jon Jun 27 '12 at 07:05biblatex.cfg. If such a file is at a place where LaTeX can found it, it will be read after the citation and bibliography styles have been loaded. – Ulrike Fischer Jun 27 '12 at 08:45\citehere is that it is context-sensitive and produces a fullcitation if the reprint is after the present entry and a abbreviated citation if the reprint is in front of the entry. Since - I think - I couldn't find\shortcitecommand, I decided to create my own:Reprint in: Author. Title, Year. My question remains for any case in which the user wants to define his own reprint-string. – ClintEastwood Jun 28 '12 at 07:36shorttitlefield, it will use that in the x-ref; and if you use an author-date system, it will use the last name and date only. Anyway, I think you can combine my idea with bibliography strings put in the .cfg file as suggested. You will not violate any licence: they are meant as '(user) ConFiGuration' files.biblatex.cfgeven has the line '% Put your definitions here.' – jon Jun 28 '12 at 07:46bibtex.cfgand put it in a local texmf tree in a similar location so that it is found first. – Ulrike Fischer Jun 28 '12 at 09:28