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22 lines
974 B
22 lines
974 B
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Exercise 3.7: Consider the bank account objects
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created by make-account, with the password modification described in
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Exercise 3.3. Suppose that our banking system requires the ability to
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make joint accounts. Define a procedure make-joint that accomplishes
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this. Make-joint should take three arguments. The first is a
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password-protected account. The second argument must match the password with
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which the account was defined in order for the make-joint operation to
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proceed. The third argument is a new password. Make-joint is to create
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an additional access to the original account using the new password. For
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example, if peter-acc is a bank account with password
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open-sesame, then
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(define paul-acc
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(make-joint peter-acc
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'open-sesame
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'rosebud))
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will allow one to make transactions on peter-acc using the name
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paul-acc and the password rosebud. You may wish to modify your
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solution to Exercise 3.3 to accommodate this new feature.
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