When running TDML files, the line numbers in the TDML file are what you want, but the schema itself is scraped off the TDML, enhanced with surrounding boilerplate, then fed to the compiler front end, which runs validation of the DFDL schema. The line numbers are therefore, quite useless.

To fix this we need to figure out (and hijack) the mechanism by which the validator determines the line numbers.

We're going to need the same tricks for our own processing of the DFDL schemas post validation.