Thanks Wolfgang. I am experimenting with your code and there has arisen a problem. The book I am typesetting has some pages before the text on page-1 starts (cover and so on). Therefore the code
    \def\mypageref[#1]{\setpagestate[hvdm][#1]\color[red]{page=\pagenumber\ and pageref=\pagestaterealpage{hvdm}{#1}}}
produces "page=29 and pageref=31". Not as intended. Do I change the macro \pagestaterealpage into what macro? I tried \pagestatepage, but that wasn't the right idea.

Now what further to change?

Hans van der Meer




On 17 Jan 2016, at 19:37, Wolfgang Schuster <schuster.wolfgang@gmail.com<mailto:schuster.wolfgang@gmail.com>> wrote:

\definepagestate[hans]

\starttext

One\setpagestate[hans][one]

\page[+2]

Two\setpagestate[hans][two]

Three\setpagestate[hans][three]

\blank

\ifnum0\pagestaterealpage{hans}{two}=0\pagestaterealpage{hans}{one}
    The references are on the same page.
\else
    The references are on different pages.
\fi

\blank

\ifnum0\pagestaterealpage{hans}{two}=0\pagestaterealpage{hans}{three}
    The references are on the same page.
\else
    The references are on different pages.
\fi

\stoptext