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C00002 00002		This short document lists the  currently outstanding problems
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	This short document lists the  currently outstanding problems
associated with the  design of HAL.  As these are solved, 4R.DOC will
be changed to  reflect the solution,  and they  will be removed  from
this list.
	RF is responsible  for this file.  Anyone may  add to it, but
please let RF do all the deleting.

	LANGUAGE FEATURES

	DATATYPES AND VARIABLES

	Need  syntax   for  graph   structure  manipulation   macros,
principally the vine-to-rake  transformation and deletion.  We should
also write down the algorithms needed.

	EXPANDER STUFF, WORLD MODELLING
	We need  a syntax  for  "let the  expander, in  his  infinite
wisdom, select a frame for me following  the constraints I have given
it". RCB: That sounds about right to me!!!

	Do  we want an ASSERT  ALWAYS construct to  make an assertion
valid for all world models during planning? RCB: Why?  save compiler
checking? save reassertions? or catching accidental changes to that
assertion?


	WRITING THE PAPER

	RCB: (NOTE that the papers for the 4th International AI Conf.
are due by October 1, 1974!!!  I think some portion of this should be
there.)

	We should somewhere in 4R.DOC  put in a section on philosophy
decisions.  Currently, these include:
	The world is plastic; things flow a bit over time.
	The  language is to be accessible  to a technically competent
factory worker.

	DETAILS OF THE RUNTIME

	We  have not  worked  out the  syntax  for the  runtime  code
driving ON monitors.

	ODDS AND ENDS