To: J3                                                     J3/19-170
From: Van Snyder
Subject: Specifications and syntax for container support
Date: 2019-June-14
References: 04-153 04-383r1 19-120 19-121 19-122 19-123 19-167 19-168
            19-169

Two PDF papers, 19-168 Containers, and 19-169 Coroutines and Iterators,
together provide specifications and syntax to satisfy all but one of the
requirements for containers that are specified in paper 19-167

19-168 satisfies the following requirements for containers specified in
19-167:

  o A representation for their persistent state,
  o Methods to initialize their persistent state, e.g.:
    - Initial size (e.g. for a stack or queue),
    - Internal parameters (e.g., dimensions of a sparse matrix),
  o Methods to enter or update elements,
  o Methods to retrieve a specified element or a pointer associated
    with one,
  o Methods to retrieve a subset of elements,
  o Methods to finalize their persistent state, and
  o Ability to declare or allocate more than one container object
    without physically copying program text, or effectively copying it
    using a device such as a parameterized module, macro, template or
    INCLUDE statement.

19-169 satisfies the following requirement specified in 19-167:

  o Methods to traverse the elements or a subset thereof.

Support for generic programming: parameterized modules, macros, or
templates, will satisfy the following requirement specified in 19-167:

  o Ability to instantiate a framework for a representation for a
    persistent state, and associated methods, for specified type
    and kind.

19-168 is a revision 19-123, assigned to JOR at meeting 218, processed
by JOR without discussion with the author, offered for vote on Thursday,
and processed with essentially no discussion.  It was clear that neither
JOR nor the committee as a whole understood the paper, and insufficient
time was allowed for discussion.

19-169 is substantially the same as 19-121, which was classified before
meeting 218 as "info," and was not processed, discussed, or voted.  I
did not submit it as a joke or only for information.  It was not
uploaded to the Tutorials directory.  It is a serious proposal to
support containers.

Nonnormative material referenced in 19-168 has been placed on the server
in the Tutorials directory, using file names that include the authors'
names:

   R. M. Burstall and R J. Popplestone, "POP-2 Reference Manual",
   Department of Machine Intelligence and Perception, University of
   Edinburgh.

   Charles M. Geschke and James G. Mitchell, "On the problem of uniform
   references to data structures," IEEE Transactions on Software
   Engineering SE-2, 1 (June 1975) 207-210.

   David Parnas, "On the criteria to be used in decomposing systems
   into modules," Comm. ACM 15, 12 (December 1972) 1053-1058.

   D. T. Ross, "Uniform referents: An essential property for a software
   engineering language," in Software Engineering 1 (J. T. Tou, Ed.),
   Academic Press, (1970) 91-101.

   R. D. Tennent, "Principles of Programming Languages" (C. A. R. Hoare
   Ed.), Prentice-Hall International Series in Computer Science (1981),
   ISBN:0137098731, page 114.

These references will be especially helpful to understand the motivation
for the design of facilities describee in 19-168.