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[gmt-dev] Re: example meta model etc.
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Hi Jorn Bettin and Ghica van Emde Boas,
May I offer my 2 cents worth to clear the perceived misunderstandings I
am beginning to sense in this thread?
At its current infancy stage, the MDA vision might be achieved by two
rather different interpretations - these two schools of thought have been
termed ?elaborationist? and ?translationist? (terms that were, I believe,
originally coined by Stephen Mellor).
In the elaborationist approach, the definition of the application is
built up gradually as you progress through from PIM to PSM to Code. Once
the PIM has been created, the tool generates a skeleton or first-cut PSM
which the developer can then ?elaborate? by adding further information or
detail. Similarly, the tool generates the final code from the PSM, and
this may also be elaborated. (Whether elaboration is required at both PSM
and Code levels depends on the tool and the circumstances.)
In the translationist approach, the PIM is translated directly into the
final code of the system by code generation. The transformation (or
translation) of the PIM into the final code is performed by a
sophisticated code generator, sometimes called a ?Model Compiler?, and
symbolised by the large arrow. It is driven by Generation Rules that
describe how the elements of the PIM are to be represented in the final
code. The PSM is an intermediate stage in the generation and is internal
to the code generator. It is generally not visible or editable by the
developer.
Does it make sense?
Y e u W e n
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\\ ^ ^ //
( @ @ )
--------------oOOo--(_)--oOOo----------
"The mere formulation of a problem is far more often essential than its
solution, which may be merely a matter of mathematical or experimental
skill. To raise new questions, new possibilities, to regard old problems
from a new angle requires creative imagination and marks real advances in
science."
Albert Einstein (1879-1955) Physicist & Nobel
