-- this file is probably obsolete --

The package system interface.  Much too complicated.

Signatures 

	  make-simple-signature
	  make-compound-signature
	  signature?
	  signature-ref
	  signature-walk

Structures 

	  make-structure
	  structure?
	  structure-signature
	  structure-package
	  structure-name

Packages

	  make-package
	  make-simple-package		;start.scm

Lookup and definition operations

	  package-lookup
	  package-lookup-type           ;comp.scm
	  package-find-location		;rts/env.scm
	  package-lookup-location	;segment.scm
	  probe-package
	  package-check-assigned
	  package-check-variable

	  package-define!
	  package-define-type!     ;hmm.
	  package-ensure-defined!

Things needed by the form/file/package scanner

	  for-each-definition           ;for integrate-all-primitives!
	  package-accesses              ;for scan-package
	  package-clauses		;for scan-package
	  package-file-name		;for scan-package
	  package-opens			;for scan-package
	  package-evaluator             ;for define-syntax
	  package-for-syntax            ;for define-syntax

Miscellaneous

          $note-undefined               ;eval.scm
	  noting-undefined-variables	;eval.scm, etc.
	  package-uid			;eval.scm
	  set-shadow-action!		;eval.scm
	  verify-later!			;for the define-structures macro
	  reset-packages-state!         ;Makefile - for linker
          initialize-reified-package!   ;for reification
	  transform-for-structure-ref   ;for reification ?

Inessential (for package mutation, programming environment)

	  check-structure
	  package-integrate?            ;env/debug.scm
	  set-package-integrate?!	;env/debug.scm
	  package-loaded?		;env/load-package.scm
	  set-package-loaded?!		;env/load-package.scm
	  package-name			;env/command.scm
	  package-name-table		;env/debuginfo.scm
	  package-open!			;env/debug.scm
	  package-system-sentinel	;env/command.scm
	  package-unstable?		;env/pacman.scm
	  package?			;env/command.scm
	  undefined-variables		;env/debug.scm

Location names (also inessential)

	  flush-location-names
	  location-name
	  location-name-table
	  location-package-name
