handling basic Makefile as domain specific language

After reading Bruce A. Tate's 7 languages book, I wondered whether it
would be possible to configure IO to support the basic dependency syntax
of Unix make. I'm not concerned with full Makefiles, just the type of
output that you get from gcc with the -M (or -MM) options and similar
tools. At worst, this might be something like:

# comment
file.o: \
  file.h \
  file.cpp

IO already accepts \ for continuation lines and # for comments so I
thought I'd just need to define : as an assignment operator but this is
where I've hit a snag.

With “file: dep”, the colon appears to be treated as part of the
identifier. However, you can happily enter 1+1 so the same problem does
not apply to “+”.  This doesn't seem to match my understanding of IO's
grammar. Trying with :=, I get the following:

Io> value:="string"

  Exception: Slot value: not found. Must define slot using := operator before updating.
  ---------
  message 'updateSlot' in 'Command Line' on line 1

Io> value := "string"
==> string

Is there any workaround for this?

I've used “call argAt(1) asString” to get the arguments in the
definition of the : operator. Is anyone aware of any parsing applied on
that argument that might prove troublesome?

Thanks

Oliver Kiddle

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