Sometimes, it is convenient if I know I am in frontmatter or bodymatter.
 
when desinging a book, we make a new chapter open at a right page and design the header to show the chapter title and pagenumber. We have to set the pagenumber at the page where a chapter title is located.
 
\definetext
  [chapterstart]
  [footer]
  [{\hfill\bf\pagenumber\hfill}]
\setuphead
  [chapter]
  [footer=chapterstart]
 
if this book consists of a frontmatter and a backmatter, I have to set the text for the titles in frontmatter and chapters in bodymatter like this, for roman pagenumber in frontmatter.
 
\startsectionblockenvironment[frontpart]
  \definetext
    [titlestart]
    [footer]
    [{\hfill\bf\romannumerals\pagenumber\hfill}]
  \setuphead
    [title]
    [footer=titlestart]
\stopsectionblockenvironment
 
\startsectionblockenvironment[bodypart]
  \definetext
    [chapterstart]
    [footer]
    [{\hfill\bf\pagenumber\hfill}]
  \setuphead
    [chapter]
    [footer=chapterstart]
\stopsectionblockenvironment 
 
so, is there a command to make me know if I am in frontmatter or bodymatter? if so, I can use only one command to achieve that setup
 
\definetext
  [chapterstart]
  [footer]
  [{\hfill\bf\ifinfrontmatter ... \else ... \fi\hfill}]
 
 
regards,
 
Tim