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Subject: Ada's definition of "task"
From: Van Snyder <Van.Snyder@jpl.nasa.gov>
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Date: Wed, 16 Sep 2015 18:42:01 -0700
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Here's Ada's definition of task, taken from the first paragraph of
clause 9 of the Ada 2012 standard:

        "Each task represents a separate thread of control that proceeds
        independently and concurrently between the points where it
        interacts with other tasks."

Thus it is an form of parallelism intermediate between Fortran's DO
CONCURRENT parallelism, and coarray parallelism.  It is not as rigidly
structured as a fork-join construct would be.