biblatex remove space after serie in reference

Question

I´m creating a new bibliography style by customizing the standard.bbx file for my master thesis. So far I had no big troubles but now I want to adjust the macro series number since this should be in parentheses. Due to the lack of information I somtimes only have a seriesor the number.

So far it works out well, unless I only have the series. Then a space between the last word of the series and the closing parentheses appeares.

Here is my new macro

\newbibmacro*{series+number}{%
    \iffieldundef{series}% Überprüfen ob series vorhanden
        {}
        {   \setunit{\addspace\bibopenparen}
            \printtext{Reihe \addcolon\space}%
            \printfield{series}
            \iffieldundef{number} % Überprüfen ob noch Bd kommt
                {\printtext{\bibcloseparen}}
                {\setunit{\addcomma\space}}
        }%
    \iffieldundef{number}%
        {}
        {   \iffieldundef{series}%
                {\setunit{\addspace\bibopenparen}}
                {}
            \printtext{Bd \adddot}
            \printfield{number}%
            \printtext{\bibcloseparen\space}
        }
  \newunit}

And here is the MWE

\RequirePackage{filecontents}

\begin{filecontents*}{my_bibfile.bib}
    @incollection{Akyar.2008,
        author = {Akyar, Bedia},
        title = {Dual Quaternions in Spatial Kinematics in an Algebraic Sense},
        pages = {373--391},
        bookpagination = {page},
        publisher = {T{\"u}bitak},
        isbn = {1010-7622},
        editor = {{Scientific and Technological Research Council of Turkey}},
        booktitle = {Turkish journal of mathematics},
        year = {2008},
        abstract = {},
        shorthand = {AKYA08},
        location = {Ankara},
        edition = {32},
        number = {4}
    }

    @book{Angeles.2007,
        author = {Angeles, Jorge},
        year = {2007},
        title = {Fundamentals of Robotic Mechanical Systems},
        url = {http://site.ebrary.com/lib/alltitles/docDetail.action?docID=10229254},
        edition = {Third Edition},
        publisher = {{Springer Science+Business Media LLC}},
        isbn = {0-387-29412-0},
        subtitle = {Theory, Methods, and Algorithms},
        shorthand = {ANGE07},
        language = {eng},
        location = {Boston, MA, USA},
        series = {Mechanical Engineering Series},
        abstract = {},
        doi = {10.1007/978-0-387-34580-2},
        file = {http://gso.gbv.de/DB=2.1/PPNSET?PPN=546653987},
        file = {http://external.dandelon.com/download/attachments/dandelon/ids/DEAGI363052149B0CFDDDC125715B0045ACDA.pdf},
        file = {http://zbmath.org/?q=an:1140.70001}
    }
\end{filecontents*}

\documentclass[fleqn]{scrreprt}

\usepackage[scaled]{helvet}
\renewcommand{\familydefault}{\sfdefault} 
\usepackage[T1]{fontenc}

\usepackage[utf8]{inputenc}

\usepackage[style=alphabetic, % Use this style 
isbn=false,
doi=false,
url=false,
maxbibnames = 4,
minbibnames = 3,
language = ngerman,
giveninits=true]{biblatex}


\bibliography{my_bibfile}

\begin{document}

\nocite{*}

\printbibliography

\end{document}

The first reference only has a number (Here (Bd. 4)). The second has a series. But bevor the closing parentheses there is a unnecessary spacing.

Answer 1

You forgot an all too important % after \printfield{series}. Adding it to your macro, eliminates the unwanted space:

\renewbibmacro*{series+number}{%
    \iffieldundef{series}% Überprüfen ob series vorhanden
        {}
        {   \setunit{\addspace\bibopenparen}
            \printtext{Reihe \addcolon\space}%
            \printfield{series}% <- here
            \iffieldundef{number} % Überprüfen ob noch Bd kommt
                {\printtext{\bibcloseparen}}
                {\setunit{\addcomma\space}}
        }%
    \iffieldundef{number}%
        {}
        {   \iffieldundef{series}%
                {\setunit{\addspace\bibopenparen}}
                {}
            \printtext{Bd \adddot}
            \printfield{number}%
            \printtext{\bibcloseparen\space}
        }
  \newunit}

The above version emphasizes the point in which your unwanted space is being generated. But, as a matter of fact, your code has other instances of potential unwanted spaces. The version below is where I'd put trailing % to avoid unwanted spaces in your macro:

\renewbibmacro*{series+number}{%
    \iffieldundef{series} % Überprüfen ob series vorhanden
        {}
        {\setunit{\addspace\bibopenparen}%
         \printtext{Reihe\addcolon\space}%
         \printfield{series}%
         \iffieldundef{number} % Überprüfen ob noch Bd kommt
             {\printtext{\bibcloseparen}}
             {\setunit{\addcomma\space}}%
        }%
    \iffieldundef{number}
        {}
        {\iffieldundef{series}
             {\setunit{\addspace\bibopenparen}}
             {}%
         \printtext{Bd\adddot}%
         \printfield{number}%
         \printtext{\bibcloseparen\space}%
        }%
  \newunit}

I must add that it might be frowned upon that the strings "Reihe" and "Bd" are hard coded to your macro as this. Biblatex offers localized bibstrings, which are also expansible, for that. Also, to redefine an existing macro, you should rather go with \renewbibmacro.