[NTG-context] LMTX problem with doifmode in \setuplayout

8 Jun 2021

      Hello all,

Odd issue with LMTX (works fine with --luatex). \doifelsemode causes a 
failure if it is used to set a simple value such as on, off, yes, no, 
..., but works with a dimension. Perhaps better illustrated by an example:

    \definemode        [aaa]
                        [keep]
    \setuplayout       [
                         marking=\doifmodeelse{aaa}{off}{on},
    %                   marking=on,
                         grid=\doifmodeelse{aaa}{yes}{no},
    %                   grid=yes,
                         bottom=\doifmodeelse{aaa}{10mm}{20mm},
                        ]
    \starttext
        This is only a test.
    \stoptext

The problem occurs whether or not the mode is enabled. In the example, 
it fails with the mode test in the either the marking= or grid= keys, 
but has no problem with it in the bottom= key.

The error message says:

    The control sequence marked <to be read again> should not appear
    between \csname and \endcsname.

pointing to the enabled \doifmodeelse line.

The same issue occurs with the following, using \doifmode:

    \definemode        [aaa]
                        [keep]
    \setuplayout       [
                         marking=on,
                         marking=\doifmode{aaa}{off},
                        ]
    \starttext
        This is only a test.
    \stoptext

This did work without complaint a few months ago.

-- 
Rik Kabel