comp.lang.ruby

Hi all,

I'm starting a project that will involve injecting instructions into
x86 assembly code. I'd like to write this tool in Ruby. In the
interest of not reinventing wheels, I'm appealing to the Ruby
community: does anyone know of some serviceable source code for
parsing x86 assembly, and ideally for editing (e.g., ability to update
offsets when an instruction is moved around)? Or perhaps someone
knows of an assembler written in Ruby that I could pilfer? My Google-
fu hasn't turned up anything.

(I know of Racc - it will be my starting point if I can't find an
existing parser)

Many thanks =)