A model for structured parallel processing in block-structured programming languages
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Other proposals to introduce multitasking in block structured programming languages have already been done 〈Van Wijngaarden; Pl/l〉. Anyhow the main points characterizing the model we propose are:
the synchronization methodology matches the hierarchical structure of block structured languages in a very natural way;
no specific synchronization tool is provided; on the contrary an environment is offered, where the opposite needs of fluidity and structuration are balanced satisfactorily.
Borrowing the politician terminology, we can conclude that we represent the moderate wing of the "fluid control" party. Our manifesto is structure in fluidity; that is, the language must allow the definition of the control regimes and strategies that the programmer thinks apt to his aim; but our opinion is that this definition must be allowed in a structured way. The loci, where the control regime definitions reside, must be easily identifiable and clearly delimited in the program; the language must suggest and naturally support such a programming technique.
This philosophy is presently being applied to the definition of a model for nondeterministic programming 〈Montangero, Pacini and Turini〉.
KeywordsStructure Parallel Processing Block Structure Language Synchronization Methodology
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