[plt-scheme] reader macros/literate programming

hi,

i've been learning Scheme for a while now, and am starting with Common
Lisp to eventually contribute to a project that will probably use it.
while discussing the relative merits of both languages, i've been
pointed to a feature of lisp, reader macros, that seems instrumental
to our work (implementing a reflective language on top of lisp)... so
i was wondering: does PLT Scheme offer functionality similar to CL's
reader macros? (mind you, i'm an absolute begginer on these and
related topics, so please forgive my not being more specific).

on a totally unrelated note, i've been using in the past noweb for
literate programming (mostly in OCaml), and was thinking of using it
with my MzScheme hacks. as you problably know, in LP, source code
files are produced from a document that contains both the source code
and its documentation intermingled. the actual source code is
automatically generated from such a document. when you
compile/interpret such generated files, it is very useful to have some
sort of #LINE directive (à la C) in the generated code which points
back to the source document/line, so that when you encounter an error,
you can easily jump back to the source document (usually, the
compiler/interpreter reports the #LINE file/lineno instead of the
source code ones)... does mzscheme offer this (or similar) functionality?

please, feel free to send me RTFM if advisable :)

thanks a lot for you help,
jao
-- 
Happiness is when what you think, what you say, and what you do are in
harmony. -Mohandas K. Gandhi (1869-1948)