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Topic: Lvalue

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	What are Lvalues and Rvalues?
		An lvalue (pronounced: L value) is an expression that refers to such an object.
		The original definition of lvalue referred to "an object that can appear on the left-hand side of an assignment." However, const objects are lvalues, and yet they cannot appear on the left-hand side of an assignment.
		An lvalue can appear in a context that requires an rvalue; in this case, the lvalue is implicitly converted to an rvalue.
	www.devx.com /tips/Tip/5696 (204 words)

	Proposed wording for rvalue reference
		The effect of the implicit conversion is the same as performing the declaration and initialization and then using the temporary variable as the result of the conversion.
		The result is an lvalue for lvalue-references or an rvalue for rvalue-references.
		then the reference is bound directly to the initializer expression lvalue in the first case, and the reference is bound to the lvalue result of the conversion in the second case.
	www.open-std.org /jtc1/sc22/wg21/docs/papers/2005/n1770.html (3237 words)

	Lecture Sixteen--webpage (Site not responding. Last check: 2007-10-03)
		In computer programming language, there is a specific name for expressions on the left-hand side of an equation, and a specific name for the right-hand side.
		Lvalue should be a place where you can put some thing into it.
		Since t is a lvalue, and you can copy the content in the lvalue “rate” into another lvalue “t”.
	asuweb.asurams.edu /whu/IntroCS/cs-web16.html (332 words)

	LValue Example (Site not responding. Last check: 2007-10-03)
		Lvalue or location value is an address that is stored into.
		In the first declaration, the array's three locations (lvalues) are initialized to the respective constants.
		We will have return types that are rvalue types, and return types that are lvalue types.
	www.cs.ucsc.edu /~pohl/code/lvalue.htm (275 words)

	Simple assignment lvalue subs should be on by default -
		Currently, there are several competing RFC's for lvalue subs, all of which do things a little differently to please different groups.
		The key to the proposal is this: lvalue and rvalue versions of a sub would work identically, and both would be enabled by default.
		Enable lvalue and rvalue versions of subs to be used interchangeably by default.
	dev.perl.org /perl6/rfc/154.html (619 words)

	RFC 118 (v2) lvalue subs: parameters, explicit assignment, and wantarray (Site not responding. Last check: 2007-10-03)
		I counter-propose that lvalue subs should receive their rvalues as lexical variables named in a prototype associated with the :lvalue modifier.
		The lvalue-ness of a given subroutine call should be discoverable with the wantarray() function (or its replacement), and the assignment behaviour should be written in the subroutine rather than implicitly done by Perl.
		Currently you must have the lvalue as the last value before the return, and the assignment is implicitly done by Perl.
	www.mail-archive.com /perl6-announce@perl.org/msg00254.html (282 words)

	Using a Function Call as an Lvalue
		An Lvalue is an expression that can appear on the left-hand side of an equals sign.
		Notice that the result type of the function is a reference, so the function may be used as an Lvalue.
		As you can see, references are not merely syntactic sugar or another way of expressing pointers, but were designed into the language by necessity to correctly hande cases such as this.
	www.devx.com /tips/Tip/29288?trk=DXRSS_recentTips (553 words)

	Semple Analysis Engine: semple::Lvalue class Reference (Site not responding. Last check: 2007-10-03)
		The Lvalue class represents expressions that evaluate to lvalues.
		Lvalues are distinguished from other expressions because they represent addresses that can be modified, e.g., by assignment or classification statements.
		The Lvalue class may not be instantiated (it is a base class for actual Semple lvalue expressions), and is represented by the grammar nonterminate
	www.cs.rpi.edu /~gregod/Semple/classsemple_1_1Lvalue.html (116 words)

	The Forwarding Problem: Arguments
		Another downside is that rvalues are forwarded as lvalues (a common trait of all presented solutions except #7).
		In the current language this is rarely a problem, but in an extended language that features the ability to overload on "rvalueness" - required to support move semantics [4] - this forwarding solution may prove less than perfect (C1).
		When f is invoked with an lvalue of type X, A1 is deduced as X and, and g receives static_cast(a1), i.e.
	www.open-std.org /jtc1/sc22/wg21/docs/papers/2002/n1385.htm (2372 words)

	Thompson's B Manual
		The names lvalue and rvalue come from the assignment statement which requires an lvalue on the left and an rvalue on the right.
		Binding of expressions (lvalues and rvalues) is in the same order as the sub-sections of this section except as noted.
		The rvalue of the string is the lvalue of the object containing the first character.
	cm.bell-labs.com /cm/cs/who/dmr/kbman.html (3811 words)

	HP OpenVMS systems - C (Site not responding. Last check: 2007-10-03)
		After evaluating this expression, the result is the incremented rvalue, not the corresponding lvalue.
		For this reason, expressions that use the increment and decrement operators in this manner cannot appear by themselves on the left side of an assignment expression where an lvalue is needed.
		The lvalue can be a function designator or any lvalue that designates an object, including an unqualified array identifier.
	h71000.www7.hp.com /commercial/c/docs/6180p016.html (1808 words)

	[No title]
		RFC 118 counter-proposes that lvalue subs should receive their rvalues as lexical variables named in a prototype associated with the :lvalue modifier.
		One group considers an lvalue return solely for assignment, and hence propose to add an additional magical parameter to lvalue routines.
		The other group joins me in the opinion that lvalue means, in essence, equivalence to a variable.
	dev.perl.org /perl6/rfc/132.pod (669 words)

	Increment and Decrement Operators (++, --)
		The operand must be a scalar lvalue — it is illegal to increment or decrement a constant, structure, or union.
		The increment and decrement operators have the same precedence, but bind from right to left.
		is not an lvalue as required by the
	docs.hp.com /en/B3901-90007/ch05s09.html (666 words)

	[Compiler-sig] Re: Lvalue (Site not responding. Last check: 2007-10-03)
		Perhaps instead of LValue we have AssignAttribute, AssignName, etc. The AST from the compiler package in the std library uses this approach, although I don't like the names it uses.
		The bytecode generated is different, and there needs to be some way for the code generator to distinguish the cases.
		Using LValue or just Expr means that the code generator needs to track context explicitly to see if the LValue is being used as an expression or an assignment.
	mail.python.org /pipermail/compiler-sig/2002-April/000115.html (295 words)

	chadr's skewed perspective : Are you an lvalue or an rvalue?
		Compiler geeks (whom I used to publicly, and now secretly, aspire to join) might think of this in terms of lvalue and rvalue (setting the value, or reading the value).
		Following Andrew's observation on the behavior of the OED, I presume I would find a set of asterisks on these slang words so that I would know, always, when I was straying from the Queen's English.
		Heather, my descriptions of lvalue and rvalue were confusing.
	blogs.msdn.com /chadroyal/archive/0001/01/01/130561.aspx (1429 words)

	Boost.Python - <boost/python/lvalue_from_python.hpp>
		Extractor whose execute function returns a reference type.
		Extracts the lvalue from the Python object once its type has been confirmed
		Extractor which can be used in the common case where the C++ type to be extracted is the same as the Python object type.
	www.boost.org /libs/python/doc/v2/lvalue_from_pytype.html (295 words)

	cast-as-lvalue
		In some cases, the pointer is typed as void, in # other cases it has a specific type, but regardless the compiler needs to # treat it as a different type when it is incrementing it.
		You can tell it's suspect without even knowing the Standard, because I could drop one line in your "derivation" and come up with the same answer where it's more obviously incorrect.
		lvalue ref char s ref ref int (int)s lvalue** ref int (int*)s
	www.codecomments.com /message264324.html (1523 words)

	IAR Systems: Expression must be a modifiable lvalue error (Technical Note 82120)
		This error message occurs because a cast does not produce an lvalue (value that can be used on the left side of an assignment).
		The reason why it does not work is that a cast does not produce an lvalue (ISO/ANSI 9899-1990 6.3.4 and Annex B which describes the syntax of C).
		From ISO/ANSI 9899-1990 6.3.4, cast operators, footnote 44: "A cast does not yield an lvalue.
	supp.iar.com /Support/?note=82120 (350 words)

	Interactive Shading Language Description
		Uniform matrix assignments take the following forms, where lvalue is either a uniform matrix variable or one element of a uniform matrix array variable, accessed as
		Uniform string assignments take the following forms, where lvalue is either a uniform string variable or one element of an uniform string array variable, accessed by
		Parameter matrix assignments take the following forms, where lvalue is either a parameter matrix variable or one element of a parameter matrix array variable, accessed as
	www.cs.unc.edu /~olano/s2001c24/ch06b.html (2647 words)

	Conditional Love: FOREACH Redux
		If the container is an lvalue (that is, a named object), we don't have to make a copy because it is not in danger of going out of scope while we iterate over it.
		We've assumed that there is some way to detect the lvalue- ness or rvalue-ness of an expression.
		If E2 is an lvalue: E1 can be converted to match E2 if E1 can be implicitly converted (clause 4) to the type "reference to T2"...
	www.artima.com /cppsource/foreach3.html (1348 words)

	lvalue - OneLook Dictionary Search (Site not responding. Last check: 2007-10-03)
		We found 2 dictionaries with English definitions that include the word lvalue:
		Tip: Click on the first link on a line below to go directly to a page where "lvalue" is defined.
		lvalue : Free On-line Dictionary of Computing [home, info]
	www.onelook.com /cgi-bin/cgiwrap/bware/dofind.cgi?word=lvalue (77 words)

	locals wordset
		Note that the identifiers are only valid inside the currently compiled word, the SEE decompiled word will show them as ...
		The return-stack-pointer will be increased only at the time of this function (and the address assigned to the LVALUE) so that the provided size gets determined at runtime.
		Note that in some configurations the forth-return-stack area is quite small - for large string operations you should consider to use a POCKET-PAD in pfe.
	pfe.sourceforge.net /manual/ch03s30.html (396 words)

	awk
		In expression evaluation, where the grammar is formally ambiguous, higher precedence operators shall be evaluated before lower precedence operators.
		The precise syntax of expressions is given in Grammar.
		An array name followed by a subscript within square brackets can be used as an lvalue and thus as an expression, as described in the grammar; see Grammar.
	www.opengroup.org /onlinepubs/009695399/utilities/awk.html (11388 words)

	awk
		In expression evaluation, where the grammar is formally ambiguous, higher precedence operators will be evaluated before lower precedence operators.
		In this table expr, expr1, expr2 and expr3 represent any expression, while lvalue represents any entity that can be assigned to (that is, on the left side of an assignment operator).
		For each occurrence of backslash (\) encountered when scanning the string repl from beginning to end, the next character is taken literally and loses its special meaning (for example, \and will be interpreted as a literal ampersand character).
	www.opengroup.org /onlinepubs/007908799/xcu/awk.html (8635 words)

	Semple Analysis Engine: Templatesemple::analysis::lvalue< T > class Reference (Site not responding. Last check: 2007-10-03)
		A simple wrapper around an function that returns an lvalue, allowing one to read and modify the lvalue easily.
		Dynamically dispatch to any function object that takes no arguments and returns an lvalue of type T. Public Member Functions
		Initialize an lvalue with the given lvalue accessor.
	www.cs.rpi.edu /~gregod/Semple/classsemple_1_1analysis_1_1lvalue.html (108 words)

	Java Forums - lvalue
		This topic has 3 replies on 1 page.
		What it wants to say lvalue in Java?
		I obtained a definition but exactly thus I continue not understanding its meaning.
	forum.java.sun.com /thread.jspa?threadID=613668&messageID=3396617 (115 words)

	Lvalue Required(wierd)...
		Please e-mail your answers to eng__wessam@gawab.com and as a follow-up to this message.
		> > What is The Lvalue Required error message.
		You need to access one of the indices, i.e.
	www.codecomments.com /message221463.html (1369 words)

	Comp.compilers: Re: Need help with grammars! (Site not responding. Last check: 2007-10-03)
		exp ::= id [..) or reduce (lvalue ::= id).
		The obvious problem is the (lvalue ::= lvalue.
		production (lvalue -> lvalue [ exp ]) which causes '[' to be in
	compilers.iecc.com /comparch/article/98-05-030 (229 words)

	ERCB: DDJ Programmer's Bookshelf October 1991
		In any dictionary like this, there is a danger of collecting a lot of formal sounding academic terms (such as "semi-Thue system"), and missing some of the more colorful jargon of computing.
		I found, however, that despite some unfortunate omissions ("lvalue" and "thunk" -- how could they leave those out?!), many of these phrases did make it into the Oxford dictionary: shell, pipeline, stub, execute, latch, lazy evaluation, Look and Feel, bit-slice, rollback, thrashing, garbage collection, remote procedure call, hash, clone, cache, and carry.
		Just skimming through a book like this will give you an appreciation for the vast number of key concepts -- contributions to human thought, in a way -- produced by the field of computing.
	www.ercb.com /ddj/1991/ddj.9110.html (2404 words)

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