Mixing
In a class constructor, define a vector of T type
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I can already define a function pointer vector with a fixed parameter type in the public: header, then update it in the constructor. But, if I want to be able to pass a function pointer vector with a parameter of any type, how can I define it before the constructor updates it?
#include <iostream>
#include <vector>
class foo {
public:
std::vector<void (*)(int)> functions;
foo(std::vector<void (*)(int)> x) {
functions=x;
}
void run() {
functions[0](2);
}
};
void square(int n) { std::cout << n*n; }
int main() {
foo* bar=new foo(std::vector<void (*)(int)>{square});
bar->run();
return 0;
}
Now, how could I pass a vector to the constructor with any type?
//snippet from above
std::vector<void (*)()> functions; //what do i do here?
template <typename T>
foo(std::vector<void (*)(T)> x) { //this works fine
functions=x;
}
c++ c++11 templates vector
edited Jan 3 at 4:32
eyllanesc
86.5k103564
asked Jan 3 at 4:24
DosisodDosisod
397
add a comment |
I can already define a function pointer vector with a fixed parameter type in the public: header, then update it in the constructor. But, if I want to be able to pass a function pointer vector with a parameter of any type, how can I define it before the constructor updates it?
#include <iostream>
#include <vector>
class foo {
public:
std::vector<void (*)(int)> functions;
foo(std::vector<void (*)(int)> x) {
functions=x;
}
void run() {
functions[0](2);
}
};
void square(int n) { std::cout << n*n; }
int main() {
foo* bar=new foo(std::vector<void (*)(int)>{square});
bar->run();
return 0;
}
Now, how could I pass a vector to the constructor with any type?
//snippet from above
std::vector<void (*)()> functions; //what do i do here?
template <typename T>
foo(std::vector<void (*)(T)> x) { //this works fine
functions=x;
}
c++ c++11 templates vector
edited Jan 3 at 4:32
eyllanesc
86.5k103564
asked Jan 3 at 4:24
DosisodDosisod
397
add a comment |
I can already define a function pointer vector with a fixed parameter type in the public: header, then update it in the constructor. But, if I want to be able to pass a function pointer vector with a parameter of any type, how can I define it before the constructor updates it?
#include <iostream>
#include <vector>
class foo {
public:
std::vector<void (*)(int)> functions;
foo(std::vector<void (*)(int)> x) {
functions=x;
}
void run() {
functions[0](2);
}
};
void square(int n) { std::cout << n*n; }
int main() {
foo* bar=new foo(std::vector<void (*)(int)>{square});
bar->run();
return 0;
}
Now, how could I pass a vector to the constructor with any type?
//snippet from above
std::vector<void (*)()> functions; //what do i do here?
template <typename T>
foo(std::vector<void (*)(T)> x) { //this works fine
functions=x;
}
c++ c++11 templates vector
edited Jan 3 at 4:32
eyllanesc
86.5k103564
asked Jan 3 at 4:24
DosisodDosisod
397
I can already define a function pointer vector with a fixed parameter type in the public: header, then update it in the constructor. But, if I want to be able to pass a function pointer vector with a parameter of any type, how can I define it before the constructor updates it?
#include <iostream>
#include <vector>
class foo {
public:
std::vector<void (*)(int)> functions;
foo(std::vector<void (*)(int)> x) {
functions=x;
}
void run() {
functions[0](2);
}
};
void square(int n) { std::cout << n*n; }
int main() {
foo* bar=new foo(std::vector<void (*)(int)>{square});
bar->run();
return 0;
}
Now, how could I pass a vector to the constructor with any type?
//snippet from above
std::vector<void (*)()> functions; //what do i do here?
template <typename T>
foo(std::vector<void (*)(T)> x) { //this works fine
functions=x;
}
c++ c++11 templates vector
c++ c++11 templates vector
edited Jan 3 at 4:32
eyllanesc
86.5k103564
asked Jan 3 at 4:24
DosisodDosisod
397
edited Jan 3 at 4:32
eyllanesc
86.5k103564
asked Jan 3 at 4:24
DosisodDosisod
397
edited Jan 3 at 4:32
eyllanesc
86.5k103564
edited Jan 3 at 4:32
eyllanesc
86.5k103564
edited Jan 3 at 4:32
eyllanesc
86.5k103564
86.5k103564
asked Jan 3 at 4:24
DosisodDosisod
397
asked Jan 3 at 4:24
DosisodDosisod
397
asked Jan 3 at 4:24
DosisodDosisod
397
397
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
You can turn the class into a class template instead
template<class T>
class foo {
public:
std::vector<void (*)(T)> functions;
foo(std::vector<void (*)(T)> x) : functions(x)
{ }
...
}
foo<int>* bar=new foo(std::vector<void (*)(int)>{square});
I would also recommend switching from a function pointer to std::function and that you don't use raw pointers. Use std::unique_ptr or one of its cousins.
answered Jan 3 at 4:35
JansJans
9,17422735
Ah, thanks, works now. Will look into making those other changes.
– Dosisod
Jan 3 at 4:40
Note that you can easily havefooof any number of parameters by changing<class T>to<class... T>
– Caleth
Jan 3 at 13:28
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
You can turn the class into a class template instead
template<class T>
class foo {
public:
std::vector<void (*)(T)> functions;
foo(std::vector<void (*)(T)> x) : functions(x)
{ }
...
}
foo<int>* bar=new foo(std::vector<void (*)(int)>{square});
I would also recommend switching from a function pointer to std::function and that you don't use raw pointers. Use std::unique_ptr or one of its cousins.
answered Jan 3 at 4:35
JansJans
9,17422735
Ah, thanks, works now. Will look into making those other changes.
– Dosisod
Jan 3 at 4:40
Note that you can easily havefooof any number of parameters by changing<class T>to<class... T>
– Caleth
Jan 3 at 13:28
add a comment |
You can turn the class into a class template instead
template<class T>
class foo {
public:
std::vector<void (*)(T)> functions;
foo(std::vector<void (*)(T)> x) : functions(x)
{ }
...
}
foo<int>* bar=new foo(std::vector<void (*)(int)>{square});
I would also recommend switching from a function pointer to std::function and that you don't use raw pointers. Use std::unique_ptr or one of its cousins.
answered Jan 3 at 4:35
JansJans
9,17422735
Ah, thanks, works now. Will look into making those other changes.
– Dosisod
Jan 3 at 4:40
Note that you can easily havefooof any number of parameters by changing<class T>to<class... T>
– Caleth
Jan 3 at 13:28
add a comment |
You can turn the class into a class template instead
template<class T>
class foo {
public:
std::vector<void (*)(T)> functions;
foo(std::vector<void (*)(T)> x) : functions(x)
{ }
...
}
foo<int>* bar=new foo(std::vector<void (*)(int)>{square});
I would also recommend switching from a function pointer to std::function and that you don't use raw pointers. Use std::unique_ptr or one of its cousins.
answered Jan 3 at 4:35
JansJans
9,17422735
You can turn the class into a class template instead
template<class T>
class foo {
public:
std::vector<void (*)(T)> functions;
foo(std::vector<void (*)(T)> x) : functions(x)
{ }
...
}
foo<int>* bar=new foo(std::vector<void (*)(int)>{square});
I would also recommend switching from a function pointer to std::function and that you don't use raw pointers. Use std::unique_ptr or one of its cousins.
answered Jan 3 at 4:35
JansJans
9,17422735
edited Jan 3 at 12:49
answered Jan 3 at 4:35
JansJans
9,17422735
answered Jan 3 at 4:35
JansJans
9,17422735
answered Jan 3 at 4:35
JansJans
9,17422735
9,17422735
Ah, thanks, works now. Will look into making those other changes.
– Dosisod
Jan 3 at 4:40
Note that you can easily havefooof any number of parameters by changing<class T>to<class... T>
– Caleth
Jan 3 at 13:28
add a comment |
Ah, thanks, works now. Will look into making those other changes.
– Dosisod
Jan 3 at 4:40
Note that you can easily havefooof any number of parameters by changing<class T>to<class... T>
– Caleth
Jan 3 at 13:28
Ah, thanks, works now. Will look into making those other changes.
– Dosisod
Jan 3 at 4:40
Ah, thanks, works now. Will look into making those other changes.
– Dosisod
Jan 3 at 4:40
Note that you can easily have
foo of any number of parameters by changing <class T> to <class... T>– Caleth
Jan 3 at 13:28
Note that you can easily have
foo of any number of parameters by changing <class T> to <class... T>– Caleth
Jan 3 at 13:28
add a comment |
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