Download THE MELD PROGRAMMING LANGUAGE USER MANUAL

MELD PROGRAMMING LANGUAGE
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some desired action differs from the superclass action, thereby making software reuse a natural
part of the paradigm.
A Note on Dataflow Programming
Data flow programming is a paradigm useful for achieving a high degree of parallel execution.
The concept behind dataflow is simple: statements (instructions, subroutines, etc.) may be
executed as soon as their inputs become available. Dataflow can take advantage of architectural
parallelism since at any given time a number of statements may be available for execution.
Dataflow programming, however, is somewhat different from normal programming because the
approach is declarative, that is, you specify the statements to be executed, but not the order of
their execution.
MELD employs the dataflow paradigm, and MELD programmers may take full advantage of
dataflow programming at the statement level (or not, if they choose). MELD’s dataflow does not
presume a particular underlying machine architecture.
For further information on dataflow and dataflow programming languages see [Wadge 85; Broy
85; Sharp 85].
A Note on the Examples
The examples in this manual show all MELD reserved words in CAPITALS and all other
program components in Mixed case. This is merely a convention, case is not significant for
MELD reserved words. Case is, however, significant for variable and selector names. The output
examples in this manual show user typein in italics and the program output in bold.
The
example
programs
are
tested
MELD
programs,
available
in
the
/proj/meld/man/examples directory. Those examples marked ‘‘Program Fragment’’ are
not complete programs.