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Gcc Error Non-template Used As Template

Not only that, there are some techniques (template meta programming or TMP) that can, under the right circumstances, improve the efficiency of the generated code. Added: trunk/gcc/testsuite/g++.dg/template/dependent-name5.C Modified: trunk/gcc/cp/ChangeLog trunk/gcc/cp/class.c trunk/gcc/cp/cp-tree.h trunk/gcc/cp/decl.c trunk/gcc/cp/parser.c trunk/gcc/cp/pt.c trunk/gcc/testsuite/ChangeLog Comment 13 Jason Merrill 2009-03-04 19:38:02 UTC Subject: Bug 29469 Author: jason Date: Wed Mar 4 19:37:43 2009 New Revision: 144621 True or False? Unsubstantiated Compute the kangaroo sequence Radius of Convergence of Infinite Series How does NumPy solve least squares for underdetermined systems? navigate here

Seriously? But in order to understand why things are the way they are, first accept these facts: A template is not a class or a function. Suppose you have a template Foo defined like this: template class Foo { public: Foo(); void someMethod(T x); private: T x; }; Along with similar definitions for the member functions: Why microcontroller takes many clock cycles to start up with PLL clock source? http://stackoverflow.com/questions/21378150/how-to-fix-compile-error-non-template-iterator1-used-as-template

template class Foo; If you can't modify Foo.cpp, simply create a new .cpp file such as Foo-impl.cpp as follows: // File "Foo-impl.cpp" #include "Foo.cpp" template class Foo; Notice that Foo-impl.cpp #includes In what atmospheric densities or pressures have aerobrakings been performed? What's the syntax / semantics for a "function template"? Also I often prefer floating point output to contain all the digits (so I can see very small differences, etc.) so I use std::setprecision when T is a floating point type.

AttributeType is a dependent template-name which is followed by angle bracket <, so the keyword template is required here to remove the ambiguity1, making it clear to the compiler that what If that's confusing, click your heels twice, think of Kansas, and repeat after me, "I will do it anyway even though it's confusing." You can trust me on this one. A user-defined conversion function template cannot have a deduced return type struct S { template operator auto() { return 42; } // error }; (since C++14) Member variable templates A Comment 8 Steven Bosscher 2007-12-16 23:20:32 UTC Waiting for DR -> SUSPENDED.

If all you want to know is how to fix this situation, read the next two FAQs. Unsubstantiated With the passing of Thai King Bhumibol, are there any customs/etiquette as a traveler I should be aware of? However there is usually no slow-down at all. http://stackoverflow.com/questions/12959250/why-am-i-getting-the-error-non-template-f-used-as-template Comment 14 Manuel López-Ibáñez 2012-04-12 13:05:16 UTC (In reply to comment #13) > Are any of the examples in this PR actually valid? > > I think G++ is correct to

On the other hand, B is dependent on template parameter T so B is called a dependent name. thanks a lot! –muffmolch Jan 27 '14 at 10:22 add a comment| Not the answer you're looking for? Tell your C++ compiler which instantiations to make while it is compiling your template class's .cpp file. (If you've already read the previous FAQ, this answer is completely symmetric with that What could I be doing wrong here?

For instance, when stringifying bools I prefer "true" and "false" over "1" and "0" so I use std::boolalpha when T is bool. Yes. Comment 15 Jason Merrill 2009-04-03 17:32:04 UTC Subject: Bug 29469 Author: jason Date: Fri Apr 3 17:31:38 2009 New Revision: 145510 URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=145510 Log: Revert: PR c++/9634 PR c++/29469 PR c++/29607 You're required to make them match in the number, order, and nature -- type/non-type, etc.

Why can't I separate the definition of my templates class from its declaration and put it inside a .cpp file? I know there are C++ defect reports asking that question so ... Comment 9 Joseph S. break; } // ...

Without this space, the C++98/C++03 compiler would see a >> (right-shift) token instead of two >'s. But most of the code in my template function is the same; is there some way to get the benefits of template specialization without duplicating all that source code? private: Underlying data_; }; Foo > x; Foo > y; However you cannot (yet) provide an unspecified template as a template parameter, such as this: template class The other solution is to leave the definition of the template function in the .cpp file and simply add the line template void foo(); to that file: // File "foo.cpp" #include

Just define your template header-files like this: // File Foo.h #ifdef USE_EXPORT_KEYWORD export #endif template class Foo { // ... }; #ifndef USE_EXPORT_KEYWORD #include "Foo.cpp" #endif And define your non-inline At this point, programmers sometimes prefix them with B::, such as: template class D : public B { public: void g() { B::Xyz x; // Bad (even though some compilers up vote 15 down vote favorite 3 This snippet (taken from this question) compiles fine with g++ (as seen), so long the template before the return type is there.

I simplified things so newbies would "get it," even if doing so offends some experts.

Chebyshev Rotation Filter columns basing on the value of other column more hot questions lang-cpp about us tour help blog chat data legal privacy policy work here advertising info mobile contact I've simplified the relevant code to produce a bare-bones example of what I'm talking about: #include #include #include template struct Foo; template Yes. For example: #include template class Foo { public: Foo(const T& value = T()); friend Foo operator+ (const Foo& lhs, const Foo& rhs) { // ... } friend std::ostream& operator<<

So templates are overloading, right? Aren't you lucky that it is no longer the case in C++11? The first function is the default case -- the code to be used when T is anything other than int or std::string: template void foo(const T& x) { // ...implementation The problem occurs because of the last two lines, where I'm just defining the static variable std::string Foo::message.

foo ::operator+ is parsed the same as foo::operator+ so still finds the member function, the parentheses prevent that. Removed: branches/gcc-4_3-branch/gcc/testsuite/g++.dg/template/dependent-name5.C Modified: branches/gcc-4_3-branch/gcc/cp/ChangeLog branches/gcc-4_3-branch/gcc/cp/class.c branches/gcc-4_3-branch/gcc/cp/cp-tree.h branches/gcc-4_3-branch/gcc/cp/decl.c branches/gcc-4_3-branch/gcc/cp/parser.c branches/gcc-4_3-branch/gcc/cp/pt.c branches/gcc-4_3-branch/gcc/testsuite/ChangeLog Format For Printing -XML -Clone This Bug -Top of page Home | New | Browse | Search | [?] | Reports more stack exchange communities company blog Stack Exchange Inbox Reputation and Badges sign up log in tour help Tour Start here for a quick overview of the site Help Center Detailed Note that the pseudo-switch statement has been replaced by a call to foo_part(): template void foo(const T& x) { // ...

template void g(T x, T y); int m = 0; long n = 1; g(m, n); Since m and n have different types, the compiler can't deduce what type to switch (typeof(T)) { // Conceptual only; not C++ case int: // ... Until then, use something like the above. Here's a free tool that transforms error messages into something more understandable.

A template is a "pattern" that the compiler uses to generate a family of classes or functions. more hot questions question feed default about us tour help blog chat data legal privacy policy work here advertising info mobile contact us feedback Technology Life / Arts Culture / Recreation Then compile with -DUSE_EXPORT_KEYWORD, or whatever equivalent compiler option lets you set a preprocessor symbol like USE_COMPILER_KEYWORD, and if/when your compiler removes support for export, just remove that compiler option. All those templates and template specializations must slow down my program, right?

Ah, the intricacies of template friends. Privacy policy About cppreference.com Disclaimers Yes. more common code that works for all T types ... } As you can see, the body of foo() now doesn't mention any particular T.