difficult error with typo in var

Describe your proposed improvement and the problem it solves.

I happened to have a typo in my var {{< var country>}} (no space between y and >)

This unfortunately causes a cryptical error:

Error running Lua:
/opt/quarto/share/pandoc/datadir/lpegshortcode.lua:112: attempt to concatenate a nil value
stack traceback:
        [C]: in function 'lpeg.match'
        /opt/quarto/share/pandoc/datadir/readqmd.lua:129: in function 'readqmd.readqmd'
        /opt/quarto/share/filters/qmd-reader.lua:13: in function 'Reader'

i could only locate by removing paragraph by paragraph from the file.

Is it somehow possible to list the line-number of the error?

Describe alternatives you've considered.