No Silver Bullet Refired Fred Brooks

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No Silver Bullet RefiredFred Brooks

• Tania Maurice

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Ce Que Nous Allons Essayer Discuter,

• Accident Essence clearer or not clearer that
  is the question
• The Philosopers Stone
• Harels Gloom Themes
• What about OO
• Reuse may be the way

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Accident Essence

• Who found it helped define these concepts? (2)
• Who found it confused them?(2)

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Accident Essence

• Comprehension
• essence is the mental crafting of the
  conceptual construct accident is its
  implementation process.

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Accident Essence Confusion

• By accidental , I did not mean occurring by
  chance, nor misfortunate, but more nearly
  incidental or appurtenant.
• What fraction of total SW effort is now
  associated with the accurate and orderly
  representation of the conceptual construct, and
  what fraction is the effort of mentally crafting
  the constructs?The Finding and fixing of flaws
  falls partly in each fraction, according to
  whether the flaws are conceptual, such as failing
  to recognize some exception, or representational,
  such as a pointer mistake or a memory allocation
  mistake.

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The Philosopherss Stone

• NSB undertakes to establish that the very nature
  of SW makes it unlikely that there will ever be
  any silver bullets. Turski , in his excellent
  reponse paperTurski and I both insist that
  pipe-dreaming inhibits forward progress and
  wastes effort.

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The Philosoperss Stone(2)

• Of all misguided scientific endeavours, none are
  more pathetic than the search for the
  philosopers stoneAnd most of us have a lot of
  sympathy for these courageous souls who try to
  achieve the impossible. Ans so it continues.
  Disserations on squaring a circle are being
  written. Lotions to retore lost hair are concoted
  and sell well. Methods to impove SW productivity
  are hatched and sell very well.

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Harel Gloom themes

• Harel percieves floom in NSB to arise from three
  themes
• 1-Sharp separation into essence and accident
• 2-Treatment of each silver bullet candidate in
  isolation
• 3-Predicting for only 10 years, instead of a long
  enough time in which to expect any significant
  impovement

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What about OO

• The attractiveness of OO approach is that of a
  multivitamin pill in one fell swoop, one gets
  them(modulatity, encapsulation, intheritance,
  hierarchical) all.It is a very promising
  concept. Then why is it not catching on?
• The only way that OO can ever be fully taken
  advantage of is if some organization, with
  enforcing powers, would set standards for using
  OO and have the ability to enforce them.

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Reuse

• The best way to attack the essence of building
  software is not to build it at all. Package
  software is only one of the ways. Program reuse
  is another
• The way I see it, in order to truly reduce the
  essential difficulty of SW you have to reduce the
  difficulty of creating SW from scratch, as at
  some point every module must be created from
  scratch.