An Annotatad Bibliography On Coinpater Program Engineering - J.D. Gannon, Editor Technical Report CSRG-24 March 1973
Dijkstra, E.W.; Go To Statement Considered Harmful;Communications of the ACM, vol.11, no.3 (Mar. 1968)
pp.147-148.
The concept of independent co-ordinates with which
to describe the progress of a process is discussed.
Such co-ordinates cannot be found if unstructured
control transfers are allowed in programming languages.
Suggestions are made for alternative constructions that
are both flexible and structured so that an independent
co-ordinate system can be maintained.
Bounce-and-skip provides the user with two
options:
1. To delay the use of the result of a test
indefinitely
2. To make the entry and exit of BEGIN-END blocks
conditional upon the last test performed.
Each test performed is coded as either neutral
(its result has already been used), successful or
unsuccessful. This indicator is matched to a list of
permissible settings of the indicator associated with
each BEGIN and END. Under a mismatch condition control
is prohibited from entering through a given BEGIN and
thus it skips the block, or control is not allowed to
exit through a given END and hence it bounces and
positions itself just after the corresponding BEGIN.
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71. Evaluation
Graham71 3*15
Graham, R.M., Clancy, G.J., and DeVaney, D.B.; A
Software Design and Evaluation System; Proceedings of
the ACM/SIGOPS Workshop on System Performance
Evaluation (April 1971) pp.200-213.
There are two primary drawbacks to modelling as a
part of the implementation process. First is the need
to construct the model separately from the system,
diverting people from the primary objective. Second is
the problem of keeping the model current as the system
primitives are re-defined.
DES makes use of a single language to describe the
object system at all levels of design and
implementation. In this way simulation goes hand-inhand
with design and the performance of the final
system may be accurately estimated before full
implementation, potentially saving a costly re-design.
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