Using a D-spec to define an action in the eval

I've worded the subject badly.

In my C-specs I am using a lot of statements like this:
C eval wRawReading = XMLRtnAttr('RawReading'))

I would very much to remove the complications and gather all of these definitions in the D-spec, like this:
D fRawReading c 'XMLRtnAttr(''RawReading''))
C eval wRawReading = fRawReading

As you know, this won't actually work, even though it compiles just dandy.

The issue I am trying to resolve is having these XMLRtnAttr() words scattered all through dozens of lines of code, hard to find, hard to proof read, and hard to use.

Any suggestions & hints would be appreciated.