Plain TeX macro to read a document in Pig Latin

Say I have a file eng.tex:

\def\encounter (#1){Hello, #1!}
\encounter (World)
\bye


I convert it to Pig Latin and save it as pig.tex:

\efday\encounterway (#1){Ellohay, #1!}
\encounterway (Orldway)
\yebay


Is there a way (e.g. header you could insert) to make TeX parse pig.tex like it was written normally in eng.tex, macros and all? (I'm not very experienced with how TeX parses and don't know where to start.)

• Is there e.g. an unpig script written in a more conventional language to demonstrate exactly what you would want changed? – Charles Staats Dec 12 '13 at 15:04
• In this simple example, one could start by \let\efday\def\let\yebay\bye. Macro names don't require changing, but the non-macro names do. – Werner Dec 12 '13 at 15:21