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Re: rvalue reference won't invoke move constructor 10 Years Ago by mike_2000_17 …'s a temporary object, i.e., an rvalue, which will bind (preferrably) to an rvalue-reference, leading to the use of move…. So, if you pass a temporary object (pure rvalue) or if you pass an rvalue-reference (e.g., from using `std::move… Re: rvalue reference won't invoke move constructor 10 Years Ago by mike_2000_17 …. Normally, a move-constructor is created with a non-const rvalue reference (i.e., with `A&&` not `const A… only real purpose that a const rvalue reference has is to prevent a const rvalue from binding to a const lvalue reference… rvalue reference won't invoke move constructor 10 Years Ago by Kristian_2 …()); // This should invoke move constructor because this object here is rvalue right? } Output is: 2 1 Sadly it should be: 2… Re: how could I pass literal as rvalue reference? 12 Years Ago by Narue Visual C++ 2010 doesn't support the current rules for rvalue references (specifically the allowance for implicit conversions). The way to do it presently in 2010 is by creating a temporary rvalue string object: [code] test_rr(std::string("this is")); [/code] Visual C++ 2011 supposedly supports the current rvalue reference rules. Re: Lvalue and Rvalue error ... 17 Years Ago by himanjim [QUOTE=joshilay]hi ... can anyone please tell what are Lvalue and Rvalue errors in c and c++ ???[/QUOTE] Lvalue means location value. And Rvalue means read value. Suppose the code is int i; i=5; here i is lvalue and 5 is Rvalue. the code 5=i; generates error lvalue required. how could I pass literal as rvalue reference? 12 Years Ago by stereomatching … &&lvalue) { std::cout<<"this is rvalue"<<std::endl; } int main() { test_rr("this…; } [/code] how could I treat "this is" as rvalue reference? The easiest way I could think is [code] std… Re: std::tuple and boost::tuple don't support rvalue reference? 12 Years Ago by stereomatching [QUOTE=;][/QUOTE] I just test it on gcc4.6.2 looks like the tuple of gcc4.6.2 support rvalue reference but visual c++ do not I hope that visual c++ could support variadic template and support rvalue reference better ASAP Lvalue and Rvalue error ... 17 Years Ago by joshilay hi ... can anyone please tell what are Lvalue and Rvalue errors in c and c++ ??? Re: Lvalue and Rvalue error ... 17 Years Ago by Grunt @joshilay I don't think you get rvalue required errors. Re: Lvalue and Rvalue error ... 17 Years Ago by ~s.o.s~ [quote=Grunt]@joshilay I don't think you get rvalue required errors.[/quote] Maybe he just wanted to know the difference between the L and R values ? Question about rvalue reference 13 Years Ago by stereomatching … && should be able to swallow the lvalue and rvalue That means I could write something like this [code] void… Re: Question about rvalue reference 13 Years Ago by vijayan121 Use std::move to convert the lvalue reference to an rvalue reference. see: [url]http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2006/n2027.html#Move_Semantics[/url] > Maybe this? [ICODE]testPF(std::move(a), std::move(b) ) ;[/ICODE] Yes. Re: Question about rvalue reference 13 Years Ago by stereomatching … my understanding, I can't gain benefit from POD with rvalue reference [code] #include<vector> struct Point { int x… std::tuple and boost::tuple don't support rvalue reference? 12 Years Ago by stereomatching …; > move_tuple( strShared ); [/code] Do C++11 make tuple assist rvalue reference? Thanks lvalue and rvalue 11 Years Ago by shanki himanshu what is lvalue and rvalue? please explain with simple example. Re: rvalue reference won't invoke move constructor 10 Years Ago by Ancient Dragon The way I understand it your move constructor is not correct. The intent of the move constructure is to move data objects from one class to another, not to mearly assign a value to the current class. See [this article ](http://msdn.microsoft.com/en-us/library/dd293665.aspx)for full explanation. [Here](http://stackoverflow.com/questions/3106110/… Re: rvalue reference won't invoke move constructor 10 Years Ago by Kristian_2 I try to change data so I can see what function was invoked in process. Same as with cout. But whatever I do, I can't call move constructor. :v Re: rvalue reference won't invoke move constructor 10 Years Ago by Kristian_2 Awesome, I didn't know that. :) Re: rvalue reference won't invoke move constructor 10 Years Ago by Ancient Dragon I understand why the move constructor is called when a function returns a class, such as CreateA(), but why isn't the move constructor called when a class is passed by value to a function, such as foo(A a)? Aren't they the same? Re: how could I pass literal as rvalue reference? 12 Years Ago by sundip I am completely unable to understand what you wants to do ? Re: how could I pass literal as rvalue reference? 12 Years Ago by stereomatching Thanks, maybe we have to wait for five years before most of the main stream compilers could support c++11 Re: how could I pass literal as rvalue reference? 12 Years Ago by Narue Five years might be a little pessimistic. Though for Visual C++ you'll probably have to wait until the version after 2011 for more complete conformance[1]. GCC is the closest that I'm aware of presently, so if you want to play with C++11 you should hop over there. [1] Some of the most anticipated features (eg. variadic templates) still aren't … Re: how could I pass literal as rvalue reference? 12 Years Ago by stereomatching [QUOTE=;][/QUOTE] [code]Some of the most anticipated features (eg. variadic templates) still aren't implemented because "it's difficult"[/code] This is one of the useful feature of c++11, we don't need to use some "horrible" work around to mimic it again I don't know how of those work around work But I am pretty appreciate … Re: Lvalue and Rvalue error ... 17 Years Ago by Salem Like [inlinecode]3 = myVariable;[/inlinecode] Will generate an lvalue error, because you can't assign to a numeric constant. You can't assign to a function, or assign to an array either. Re: Lvalue and Rvalue error ... 17 Years Ago by ~s.o.s~ Yes what Mr. Salem has said is perfect and if you want a more detailed account then you can try here. [URL="http://msdn2.microsoft.com/en-us/library/bkbs2cds.aspx"]http://msdn2.microsoft.com/en-us/library/bkbs2cds.aspx[/URL] Hope it helped, bye. Re: Question about rvalue reference 13 Years Ago by Insensus Maybe this? [CODE=c++]testPF(std::move(a), std::move(b))[/CODE] Re: std::tuple and boost::tuple don't support rvalue reference? 12 Years Ago by vijayan121 The absence of variadic templates is the fundamental problem with Microsoft C++. It surfaces in several different places posing as different problems. This is (in effect) what the IS says: [CODE]template< typename... TYPES > tuple<TYPES...> std::make_tuple( TYPES&&... args ) ; returns std::tuple<TYPES...>( std::… Re: std::tuple and boost::tuple don't support rvalue reference? 12 Years Ago by stereomatching [QUOTE=;][/QUOTE] I test some of your codes on [url]http://www.daniweb.com/software-development/cpp/threads/392114[/url] it works!!!Variadic template is too powerful Now I am thinking how to implement IndexOf by it Why standard committee didn't add this feature into C++03? Because the technique was not yet mature? Or TMP was too advanced … Re: lvalue and rvalue 11 Years Ago by rithish http://publib.boulder.ibm.com/infocenter/comphelp/v8v101/index.jsp?topic=%2Fcom.ibm.xlcpp8a.doc%2Flanguage%2Fref%2Flvalue.htm Getting Fatal error 9 Years Ago by GingerDontCare …($num1, $num2) { $rValue = $num1 + $num2; return $rValue; } public function subtract($num1, $num2) { $rValue = $num1 - $num2; return $rValue; } public function multiply($num1, $num2) { $rValue = $num1 * $num2…