第8页 - 关于templating的讨论汇总 - 话题女王

全部话题 - 话题: templating

j*******e
发帖数: 674

来自主题: Programming版 - C++ class template specialization question

Thanks for the replies.
I also posted at stackoverflow.com. Their answer is:
The template is not instantiated, so the compiler has the option to report
an error or not. A guy was saying this is actually a very useful feature.

r*******y
发帖数: 1081

来自主题: Programming版 - template

template void f(vector::iterator){}
this can not compile because of vector::iterator in the parameter
list. Why this parameter is not allowed here? Thanks.

t****t
发帖数: 6806

来自主题: Programming版 - template

template void f(typename vector::iterator) {}

C***y
发帖数: 2546

来自主题: Programming版 - C++ function template问题

我有两个function，一个传入pointer，另外一个传入refernce
例如：
void func(int& a);
void func(double* a);
有办法为这两个function写一个function template吗？
Thanks!

C***y
发帖数: 2546

来自主题: Programming版 - C++ function template问题

Inside the functions, code is exactly the same.
I can use overloading, but it will duplicate the code. That's why I was
wondering if I can use template instead.
Thanks!

X****r
发帖数: 3557

来自主题: Programming版 - C++ function template问题

I'm curious how "int&" and "double*" are used exactly the same?
Anyhow, if this is indeed the case, you can write
template void func(T a) {
//...
}
However, note that this may not work as you expected: to invoke
T=int&, you're likely to need to write "func(x)" for int x,
because by default T=int for int x.

n*****3
发帖数: 1584

来自主题: Programming版 - c++ template是不是跟Macro一个道理？

I think template is implemented based on macro.
but when you doing the programming, things are
complete different.

a********m
发帖数: 15480

来自主题: Programming版 - c++ template是不是跟Macro一个道理？

类似但是不一样。template是根据类型，用到的时候产生对应代码。macro基本是字符
串替换。

s********e
发帖数: 158

来自主题: Programming版 - 关于gdb调试c++ template的问题, 设置行号断点有offset

测试了一下用g++就好了，用了intel的libirc.a解决了_intel_fast_memcpy的问题，
然后用g++编译的程序用gdb就好了，貌似是intel的问题，大家都用intel的编译器和
idb吗，如果对template支持这么差，怎么用？还有idb不能tab补全，

h**********c
发帖数: 4120

来自主题: Programming版 - C++ template preprocessor

Try to figure it out but failed,as the following:
void takefloat (float * ) {}
void takedouble (double *) {}
template
void dosomething (T * pt)
{
#if sizeof(T) == sizeof(float)
takefloat (pt);
#else
takedouble(pt);
#endif
}
Compilation failed.

A**u
发帖数: 2458

来自主题: Programming版 - C++ template preprocessor

我觉得，你这个不行的原因在
#if sizeof(T) == sizeof(float)
sizeof(T)要运行时才知道
你改成
#if XXX
#else
#endif
编译时候加上 g++ -DXXX 选择float, g++ 选择double
或者
你改成void take (float * ) {}
void take (double *) {}
template
void dosomething (T * pt)
{
take(pt);
}
这样可行吗

t****t
发帖数: 6806

来自主题: Programming版 - C++ template preprocessor

for metaprogramming, there is no "if". condition is always implicit. for
your example (as a simple function), you should write:
void dosomething(float* pt) { takefloat(pt); }
template void dosomething(T* pt) { takedouble(pt); }
although you may really want to write
void dosomething(float* pt) { takefloat(pt); }
void dosomething(double* pt) { takedouble(pt); }

h**********c
发帖数: 4120

来自主题: Programming版 - C++ template preprocessor

A**u
发帖数: 2458

来自主题: Programming版 - C++ template preprocessor

t****t
发帖数: 6806

来自主题: Programming版 - C++ template preprocessor

g****y
发帖数: 436

来自主题: Programming版 - C++ template function type

请问下面MAPPER的type应该如何写？先谢过了！
//hist_helper.h
namespace hist_aux {
template<
typename C,
typename T,
typename MAPPER
>
void getHist(const T& vals,
MAPPER pf,
C& res) {

typename T::const_iterator it;
for (it = vals.begin(); it != vals.end(); ++it) {
res.at(pf(*it))++;
}
}
} /* namespace hist_aux */
namespace hist{
class Hist {
public:
// ctr & dtr
// ...

size_t count_mapper(size_t v);
size_t index_mapper(size_t v);
size_t pixe... 阅读全帖

X****r
发帖数: 3557

来自主题: Programming版 - C++ template function type

The point is exactly not to explicitly write the type of any
template parameter and let the compiler deduces them.
Just call histo(...)

f*********y
发帖数: 376