Concurrent Prolog - Vol. 2: Collected Papers
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- Resource Analysis in the COSTA System.
- Melanie Klein in Berlin: Her First Psychoanalyses of Children (The New Library of Psychoanalysis).
- Puzzles in Wood: Simple Patterns for Creating 45 Classics.
- Advanced Data Models.
Click on an option below to access. Log out of ReadCube. We discuss P , our implementation of a tool that allows interoperation between a concurrent superset of the Prolog programming language and C. This enables Prolog to be used as a native implementation language for Microsoft's.
US6161121A - Generic transfer of exclusive rights - Google Patents
NET platform. P compiles a linear logic extension of Prolog to C source code. We can thus create C objects from Prolog and use C 's graphical, networking and other libraries. We add language constructs on the Prolog side that allow concurrent Prolog code to be written. A primitive predicate is provided that evaluates a Prolog structure on a newly forked thread.
Communication between threads is based on the unification of variables contained in such a structure. It is also possible for threads to communicate through a globally accessible table. We discuss two software engineering tools implemented using P. Volume 34 , Issue 9.
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Jonathan J. Cook Corresponding Author E-mail address: Jon. Search for more papers by this author. Tools Request permission Export citation Add to favorites Track citation.
Concurrent prolog : collected papers
Share Give access Share full text access. As of the point in the transfer shown in FIG. Once the agreement is made, party B uses a page goods description object "GDP P that is in synergy represented as a dashed line with the Page P. B must trust that the goods description GDP P will not only grant these rights, but rescind these rights from all others. B may have been constructed already knowing the particular goods description as one that it should trust;.
B may get it i. B may obtain a reference to a goods description by means that do not imply trust, but then ask another object that it already does trust and that is in synergy with certain goods descriptions whether the goods description should be trusted;. B may use a platform primitive, such as "instanceof" or a narrow operation, to check that the goods description is a particular implementation that it trusts; and.
B may grant the goods description the benefit of the doubt for inconsequential transactions, and come to invest more trust in it over time as it continues to seem trustworthy. This message is represented as "B. After receiving the message 3 , party B B attempts to acquire the agreed-upon rights to the page of memory P P. This message is represented as "GDP. The outcome of the execution of the acquire method P-1 are shown in FIG. Because the Page P is an instance of the Page class P, the acquire method P-1 successfully returns to B B a new Page instance Page-new P' that represents an exclusive right to the page of memory P P transferred from the old Page P.
As shown in FIG. The preceding description assumes that A A is transferring all of its exclusive rights to the good P P to B B. However, the situation commonly arises where a party, such as A A, needs only to transfer a portion of its rights. This is an example of why B might acquire exclusivity on only a subset of the rights made available to it, and why A may be willing to make available the ability to exclusively acquire more rights than are actually taken. Once A considers the transaction complete, it can engage in this same procedure yet again to regain exclusive access to the remaining money.
Thus, the present invention allows two parties to agree to a transfer of exclusive rights and implement that transfer in a way that guarantees that the transfer occurs. Moreover, due to the synergy between GoodsDesc instances and RescCapability instances, the present invention can be used to transfer exclusive rights to any kind of goods for which exclusive rights can be represented in a computer. For example, the present invention is adaptable to the situation shown in FIG. As in many commercial transactions between mutually-suspicious participants, A and B have agreed to accomplish this transaction through a trusted escrow agent E E.
A survey of PARLOG and Concurrent Prolog: The integration of logic and parallelism
To effect the transfer, trusted goods descriptions P and M have been created respectively by B B and A A, each of which is in synergy with a corresponding RescCapability instance As one of the first steps in effecting the transfer, party A A sends the escrow agent a message "post Page, GDM " 1a that includes references to the rescindable capability Page through which A holds P P and the goods description GDM that can acquire the money goods M M that A has bargained for in return for the page P P. Thus, following steps 2a and 2b, the escrow agent E holds references to a Money-new M' that holds on to the rights M formerly exclusively held by party B B and to a Page-new P' that holds on to the rights P formerly exclusively held by party A A.
Note that the escrow agent E is not concerned about the type of goods for which rights are being transferred. That is only a concern of the goods description objects , which actually acquire rights. Rather, the escrow agent E is only concerned that each party to the transaction has provided it with the agreed goods as represented by a non-null return value from the respective acquire methods.
Assuming that each acquire method has returned a non-null value, the escrow agent E E completes the agreed exchange by issuing "accept" messages to party A A and party B B.
The accept message issued to party A A "accept Money-new " passes the new rescindable capability Money-new M' to A that encompasses rights to the money M transferred from party B B. The accept message issued to party B B "accept Page-new " passes the new rescindable capability Page-new P' to B that encompasses rights to the page P transferred from party A A. An important aspect of these transfers as performed in the present invention is that at no time does an object with a rescindable right to a good ever directly hold on to the good.
This is what enables true rescindability. Thus, the present invention, which enables the transfer of exclusive rights to generic goods, has wide applications in electronic commerce. The present invention also is applicable to the management of computer systems, where, for example, the exclusive rights to access different computer system resources can be transferred directly, or when the parties to an exchange are mutually mistrustful transferred via trusted escrow agents who need to know nothing about the goods being transferred. While the present invention has been described with reference to a few specific embodiments, the description is illustrative of the invention and is not to be construed as limiting the invention.
Various modifications may occur to those skilled in the art without departing from the true spirit and scope of the invention as defined by the appended claims. Effective date : A system and method are disclosed that enable exclusive rights in generic goods to be transferred from one party to another.
A party holds an exclusive right to a good through a rescindable capability. When two parties agree on a transfer of the exclusive right to the good, a goods description memorializing the agreement is created which is in synergy with the rescindable capability.
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The goods description includes an acquire method that is the only method that can extract rights from the rescindable capability with which it is in synergy. The object from which the generic right is being transferred sends a message to the recipient with a reference to the rescindable capability. Upon receiving the message, the recipient invokes the acquire method of the referenced goods description, which returns a new rescindable capability that encompasses the generic right just transferred.
Once the recipient holds a reference to the new rescindable capability, the sender has had its rights rescinded. Because details of a transfer are implemented between a rescindable capability and a goods description, rights to goods of any type can be transferred. This is useful in escrow transactions, where a trusted third party with no knowledge of goods being exchanged can effect exchanges of exclusive rights to generic goods by two mutually-suspicious parties.
Thus, the preferred embodiment includes the following objects program objects instances of a variety of classes that make up the various programs , rescindable capabilities instances of the RescCapability classes , goods instances of the Good classes ; and goods descriptions instances of the GoodsDesc classes These classes , , are now described. B may have been constructed already knowing the particular goods description as one that it should trust; 2.
B may obtain a reference to a goods description by means that do not imply trust, but then ask another object that it already does trust and that is in synergy with certain goods descriptions whether the goods description should be trusted; 4. B may use a platform primitive, such as "instanceof" or a narrow operation, to check that the goods description is a particular implementation that it trusts; and 5.
What is claimed is: 1. A system that provides generic transfer of exclusive rights, comprising: a rescindable right to part or all of a generic good represented as a first program object encapsulating said rescindable right;.