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44 lines
2.3 KiB
44 lines
2.3 KiB
2 years ago
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Exercise 2.74: Insatiable Enterprises, Inc., is
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a highly decentralized conglomerate company consisting of a large number of
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independent divisions located all over the world. The company’s computer
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facilities have just been interconnected by means of a clever
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network-interfacing scheme that makes the entire network appear to any user to
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be a single computer. Insatiable’s president, in her first attempt to exploit
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the ability of the network to extract administrative information from division
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files, is dismayed to discover that, although all the division files have been
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implemented as data structures in Scheme, the particular data structure used
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varies from division to division. A meeting of division managers is hastily
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called to search for a strategy to integrate the files that will satisfy
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headquarters’ needs while preserving the existing autonomy of the divisions.
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Show how such a strategy can be implemented with data-directed programming. As
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an example, suppose that each division’s personnel records consist of a single
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file, which contains a set of records keyed on employees’ names. The structure
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of the set varies from division to division. Furthermore, each employee’s
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record is itself a set (structured differently from division to division) that
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contains information keyed under identifiers such as address and
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salary. In particular:
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Implement for headquarters a get-record procedure that retrieves a
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specified employee’s record from a specified personnel file. The procedure
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should be applicable to any division’s file. Explain how the individual
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divisions’ files should be structured. In particular, what type information
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must be supplied?
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Implement for headquarters a get-salary procedure that returns the
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salary information from a given employee’s record from any division’s personnel
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file. How should the record be structured in order to make this operation
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work?
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Implement for headquarters a find-employee-record procedure. This
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should search all the divisions’ files for the record of a given employee and
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return the record. Assume that this procedure takes as arguments an employee’s
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name and a list of all the divisions’ files.
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When Insatiable takes over a new company, what changes must be made in order to
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incorporate the new personnel information into the central system?
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