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	Referential transparency - Wikipedia, the free encyclopedia
		While in mathematics all functions are referentially transparent, in programming this is not always the case.
		The importance of referential transparency is that it allows a programmer to reason about program behavior.
		Referential transparency will cause as a side effect that no difference is made or recognised between a reference to a thing and the corresponding thing itself.
	en.wikipedia.org /wiki/Referential_transparency (295 words)

	Transparency Printing -- Recommendations and Resources (Site not responding. Last check: 2007-11-06)
		Thus, the meaning of ''transparency'' in optics is the one from which the others senses evolved.
		A transparent latch is an electronic data storage device with a data input (D), an enable input (E) and a data output (Q).
		Transparency is http://www.mail-archive.com/cypherpunks@minder.net/msg81918.html sometimes confused with equiveillance (the balance between surveillance and sousveillance).
	www.becomingapediatrician.com /health/150/transparency-printing.html (1026 words)

	Referential transparency - Encyclopedia.WorldSearch (Site not responding. Last check: 2007-11-06)
		In computer programming, a referentially transparent function is one that, given the same parameter(s), it always returns the same result.
		Referential transparency is important because it allows the programmer to reason about program behavior.
		This can help in proving correctness, finding bugs that could not be found by testing, simplifying the algorithm, assisting in modifying the code without breaking it, or optimizing the code (by means of memoization).
	encyclopedia.worldsearch.com /referential_transparency.htm (194 words)

	Transparency - Wikipedia, the free encyclopedia
		Transparency (optics), where a transparent object is one that can be seen through
		Linguistic transparency, a term used in linguistics and the philosophy of language
		Transparency (overhead projector), a thin sheet of transparent material for use with an overhead projector
	en.wikipedia.org /wiki/Transparency (180 words)

	Referential transparency (Site not responding. Last check: 2007-11-06)
		In computer programming, a referentially transparent function is one that, given the same parameter (s), it always returns the same result.
		Transparency International - Bangladesh The Bangladesh chapter of Transparency International non-governmental organization committed to countering corruption in international business transactions and, through its national chapters, to curbing corruption at the national level.
		Universal Transparency Explores the feasibility of a future surveillance society in which everyone has access to all the surveillance ("universal transparency of surveillance"); articles, forum, related books, links to related pages.
	www.serebella.com /encyclopedia/article-Referential_transparency.html (443 words)

	referential transparency (Site not responding. Last check: 2007-11-06)
		An expression E is referentially transparent if any subexpression and its value (the result of evaluating it) can be interchanged without changing the value of E. This is not the case if the value of an expression depends on global state which can change value.
		Referentially transparent programs are more amenable to formal methods and easier to reason about because the meaning of an expression depends only on the meaning of its subexpressions and not on the order of evaluation or side-effects of other expressions.
		We can stretch the concept of referential transparency to include input and output if we consider the whole program to be a function from its input to its output.
	www.linuxguruz.org /foldoc/foldoc.php?referential+transparency (440 words)

	Referential Transparency (Site not responding. Last check: 2007-11-06)
		An essential advantage of referential transparency in programming languages is that mathematical reasoning is available for referentially transparent programs (which includes a fortiori all programs written in a referentially transparent programming language).
		"The phrase 'referentially transparent' is used to describe notations where only the meaning (value) of immediate component expressions (sentences/phrases) is significant in determining the meaning of a compound expression (sentence/phrase).
		In functional languages, referential opaqueness is forbidden and referential transparency is mandatory.
	www.cas.mcmaster.ca /~kahl/reftrans.html (449 words)

	Citations: Nondeterminism with referential transparency in functional programming - Burton (ResearchIndex) (Site not responding. Last check: 2007-11-06)
		Two approaches to retain referential transparency in a language with a nondeterministic primitive is to either consult an oracle or to return an abstract data type representing all possible result values and to restrict the access to this data structure.
		....their implementations in [2, 3] Two approaches to retain referential transparency in a language with a nondeterministic primitive is to either consult an oracle or to return an abstract data type representing all possible result values and to restrict the access to this data structure.
		In, the potentially non referentially transparent features of amb and Henderson s merge are avoided through the introduction of a new data structure, oracles.
	citeseer.ist.psu.edu /context/205571/0 (2139 words)

	Referential Transparency, was Re: fluid-let
		A context C[] is "purely referential" iff C[x] means the same as C[y] whenever x and y are expressions that refer to the same object.
		Note that "purely referential" is a sub-case of "referentially transparent" (let C be the empty context or the identity function), and the second definition is needed only in case D[] is a context that does not take a term.
		referentially transparent = free variables in the macro definition are bound in the context of the definition, not by declarations in the context of the call.
	sources.redhat.com /ml/guile/1998-08/msg00401.html (411 words)

	From Perl Monks: "pissed off about functional programming" \| Lambda the Ultimate
		Referential transparency is a property of contexts, not generally of languages.
		Sestoft has a paper (Referential transparency, definiteness, and unfoldability) that attempts to extend the definition of referential transparency to apply to languages in a useful way, though I have my reservations about it.
		Referential integrity is one aspect to FP, since we are trying to use the well-driven road of functions as they are treated in the maths (where side effects are not usually allowed).
	lambda-the-ultimate.org /node/view/678 (8341 words)

	Meta-Semiotics, Reasoning, and Identities
		The notations of referential transparency and referential opacity are common in discussions of properties of programming languages.
		The notion of substitution used for referential transparency is term substitution, not text substitution: Subtituting "7 + 5" for "12" in "1 × 12 × 2" changes the expression's value from 24 to 17 ("1 × 7 + 5 × 2").
		The notion of referential transparency is significant, as it captures the property taken for granted in mathematical language, that expressions denote the same values regardless of context.
	www.cs.mun.ca /~ulf/gloss/meta.html (2814 words)

	Referential transparency -- Facts, Info, and Encyclopedia article (Site not responding. Last check: 2007-11-06)
		While in (A science (or group of related sciences) dealing with the logic of quantity and shape and arrangement) mathematics all functions are referentially transparent, in programming this is not always the case.
		For example, take a "function" that takes no parameters and returns input from the (Device consisting of a set of keys on a piano or organ or typewriter or typesetting machine or computer or the like) keyboard.
		Some (Click link for more info and facts about functional programming) functional programming languages enforce referential transparency for all functions.
	www.absoluteastronomy.com /encyclopedia/R/Re/Referential_transparency.htm (223 words)

	Referential transparency (Site not responding. Last check: 2007-11-06)
		While in mathematics all functions are referentially transparent in this is not always the case.
		Because it the programmer to reason about program behavior can help in proving correctness finding bugs that couldn't be found testing simplifying the algorithm assisting in modifying the code without it or even finding ways of optimizing it.
		In the wake of major corporate scandals over the past few years, "The Transparency Edge" is cutting-edge reading for every business executive.If all companies took this book to heart, we could have avoided the financial fiascos at Enron, WorldCo...
	www.freeglossary.com /Referential_transparency (445 words)

	Why is it called "referential transparency"?
		A (propositional) context in which a term occurred was said to be referentially opaque if when you substitute a term with the same reference for that occurrence, the truth value of the proposition can change.
		Transparency pops up in distributed relational database jargon, not sure if referential is one, essentially meaning that the operations of the database are indistinguishable from a single server.
		Contexts that are not referentially transparent might be said to depend on more than the reference of their subexpressions, and one might ask what that might be.
	www.codecomments.com /message182656.html (1362 words)

	CSC 330 Lecture Notes Week 10 (Site not responding. Last check: 2007-11-06)
		Referential transparency means that within a given context, multiple occurrences of an expression all have the same value.
		Given referential transparency, it is possible to evaluate each of the big computations concurrently.
		We noted above that referential transparency implies that any occurrence of the same expression in the same environment need only be evaluated once.
	www.csc.calpoly.edu /~gfisher/classes/330/lectures/10.html (1805 words)

	CS312 Lecture 17: Side Effects. References.
		"Referential transparency" means that at any time, any expression can be replaced with its value (and any value can be replaced with an expression that evaluates to the respective value) without changing the semantics of the program at hand.
		Referential transparency makes is easier for us to understand functional programs.
		It is clear that if our functions had "memory" and could distinguish between their various executions, then the order of function calls becomes critical and the simple world of referential transparency is lost.
	www.cs.cornell.edu /courses/cs312/2004fa/lectures/lecture17.htm (1437 words)

	Re: Referential Transparency (Site not responding. Last check: 2007-11-06)
		Hi, As far as I understood the matter, referential transparency denotes the property of a language, in which variables of the same scope do not change their value.
		Monads are fine to encapsulate effects, and so the IO Monad encapsulates input/output effects _to preserve_ the referential transparency of _the rest_ of the program.
		Prev: Re: Referential Transparency (was Re: OO in Haskell)
	www.dcs.gla.ac.uk /mail-www/haskell/msg02257.html (162 words)

	4 Evaluation
		The main features found in most declarative languages are referential transparency, strong typing and algebraic data types, polymorphism, higher order functions, and lazy evaluation.
		Another advantage of referential transparency is that it makes it easier to understand how a program works because there are no global variables that can effect the behaviour of functions.
		According to Simon Peyton Jones, declarative languages offer ``interesting opportunities for parallel execution.''[17] This is mainly due to their ability to guarantee referential transparency -- making it easy for a compiler to analyse the program and parallelise the code.
	www.cs.mu.oz.au /~dmo/se-litreview/node4.html (1286 words)

	Encyclopedia: Referential transparency
		Wikibooks has more about this subject: Computer programming Computer programming (often simply programming) is the craft of implementing one or more interrelated abstract algorithms using a particular programming language to produce a concrete computer program.
		Functional programming is a programming paradigm that treats computation as the evaluation of mathematical functions and is used in a kind of parallel programming.
		In computing, idempotence is the quality of something that has the same effect if used multiple times as it does if used only once, similarly to the idempotence notion in mathematics.
	www.nationmaster.com /encyclopedia/Referential-transparency (613 words)

	No Title
		It is often argued that referential transparency makes it easier to reason about the properties of programs.
		More importantly though, referential transparency is essential for certain compiler optimizations to be valid.
		Most dramatically, ``updating'' data structures in a referentially transparent way usually involves making a copy of the entire structure (although finding ways around this is still the subject of much research).
	www.cis.upenn.edu /~cis500-1/lectures/lec4 (1610 words)

	[No title] (Site not responding. Last check: 2007-11-06)
		Referential transparency is an oft-touted property of (pure) functional languages, which makes it easier to reason about the behavior of programs.
		I don't think there is any formal definition, but it usually means that an expression always evaluates to the same result in any context.
		C and ML are languages with constructs that are not referentially transparent.
	www.haskell.org /hawiki/ReferentialTransparency?action=raw (238 words)

	Referential Transparency (was Re: OO in Haskell) (Site not responding. Last check: 2007-11-06)
		I just can't see how if the result of an action is dependent on unknown external world agents (as it is with the IO monad) it could be described as referentially transparent.
		I can accept that we have referential transparency for user defined monads, but not the IO monad.
		One of the reasons was that apparently this would result in loss of referential transparency.
	www.dcs.gla.ac.uk /mail-www/haskell/msg02223.html (310 words)

	Effects Checking in a Functional Database Language
		Our approach is to accept that a change of database state will result in loss of global referential transparency but that referential transparency can be scoped so that areas of a program can be identified which retain the property.
		Put simply, referential transparency means that every instance of a particular variable has the same value within its scope of definition.
		Referential transparency in Relief is scoped by the update operations which destroy reference.
	www.dcs.bbk.ac.uk /TriStarp/pubs/publ.paul.html (5444 words)

	referential integrity \| TutorGig.co.uk - The Tutorial Website (Site not responding. Last check: 2007-11-06)
		Referential integrity broken.PNG right 250px thumb An example of a database that has not enforced referential integrity.
		In this example, there is a foreign key arti..." >Referential integrity, Referential Integrity DRI is a SQL Server term specifically applying to the assigning of permissions to users on a database object.
		Referential transparency..." >Referential transparency, Referential integrity compu stub...In a relational database, entity integrity is a property that ensures that no records are duplicated" >Entity integrity (More...
	www.tutorgig.co.uk /searchtgig.jsp?keywords=referential+integrity (602 words)

	Citations: definiteness and unfoldability - Sondergaard, Sestoft (ResearchIndex) (Site not responding. Last check: 2007-11-06)
		Referential transparency and related issues were studied in detail in
		It was recognized in [2] that one might have to give up referential transparency in order to adequately deal with nondeterminism.
		Although similar to oracles (Section 5) it avoids having to record choices in pseudo data to catch the cases where a non deterministic expression is accidentally copied during compilation, say.
	citeseer.ist.psu.edu /context/207399/0 (1035 words)

	CS334 Lecture 2
		Meaning of a (pure) expression is operation which, based on current contents of memory, and explicit values supplied to it, returns a value.
		Referential transparency: System is referentially transparent if, in a fixed context, the meaning of the whole can be determined solely by the meaning of its parts.
		Program supporting referential transparency much easier to prove correct since only need be concerned about meaning of components and then put them together.
	www.cs.williams.edu /~kim/cs334.97/Lec2.html (1643 words)

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