On Revival of Algol-Concepts in Modern Programming and Specification Languages - Formal Methods and Hybrid Real-Time Systems - page 430

the kind above and those from algorithmic logic [MiSa87] transfer to ASM-logic.
Furtheron: Parallel and concurrent executions are not yet integrated in the above
mentioned completeness results. See [Lan04] for more detailed expositions.

4Con lu on

It is the systematic usage of the block concept with its far reaching consequences
for nested, recursive and formal procedures what is distinguishing Algol60 as
compared to its language predecessors Fortran and Algol58. Algol60's progress
was so dramatic that later language developers in the 1970s to 1990s were very
hesitant to allow an unrestricted block concept. We see this attitude even in
the 1990s with the authors of original Java [GJS96] and of Basic ASM [Gur88,
Gur91]. After several years of experience both Java- and ASM-researchers found
out that they should allow the block concept together with recursion at any
reasonable place of a program or specification. The researchers could have had
an easier and more continuous approach to semantics definitions, implementation
techniques and verification methods if they would have respected more closely
all the experiences with Algol in the 1960s and 1970s. Nevertheless revival of
Algol-concepts demonstrates their inherant importance.
The author of this essay would like to thank for being invited to contribute
to the Festschrift to honour our colleagues Dines Bjørner and Zhou Chaochen.
Furtheron the author would like to thank Annemarie Langmaack for typesetting
of this essay.

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