Btukfyl

Given the following example using the tikzmark library:

documentclass{article}



usepackage{tikz}

usetikzlibrary{tikzmark}

usepackage{atbegshi}



AtBeginShipout{AtBeginShipoutUpperLeft{%

    foreach n in {A,B} {%

        ifnumarabic{page}=tikzmarkpage{n}

            tikz[remember picture, overlay]

                node[draw=blue] at (pic cs:n) {n};

        fi

    }

}}



newcommandtikzmarkpage[1]{%

    % How to return the actual page number of marker #1 here?

    arabic{page}%

}



begin{document}

tikzmark{A}

newpage

tikzmark{B}

end{document}

In this version the marks A and B are defined on different pages, but looping through all nodes in the AtBeginShipout hook makes all nodes being displayed on every page on top of each other. I know tikzmark already stores the page number the marker was defined on, I don't see a way to extract that information to use it for a check in the foreach loop, though.

So how would you define tikzmarkpage to get the corresponding page number for the given marker name?