Expected primary-expression before ‘&’ token
-1
I receive this error that makes it difficult for me to continue coding, because I tried and tried to solve it and was unable to understand what the error means (I looked at similar questions in Stackoverflow).
I do not understand why, if I declare a set of Node objects as a type of data, I get these errors, code:
point p(p.get_x(),p.get_y());
Node a(p,0);
set<Node&> visited_nodes;
The error:
error: expected primary-expression before ‘&’ token
set<Node&> visited_nodes;
^
error: expected primary-expression before ‘>’ token
set<Node&> visited_nodes;
Thanks
c++ oop object compilation set
edited Nov 11 '18 at 22:35
Matthieu Brucher
15.6k32140
asked Nov 11 '18 at 22:12
AERAER
11317
add a comment |
-1
I receive this error that makes it difficult for me to continue coding, because I tried and tried to solve it and was unable to understand what the error means (I looked at similar questions in Stackoverflow).
I do not understand why, if I declare a set of Node objects as a type of data, I get these errors, code:
point p(p.get_x(),p.get_y());
Node a(p,0);
set<Node&> visited_nodes;
The error:
error: expected primary-expression before ‘&’ token
set<Node&> visited_nodes;
^
error: expected primary-expression before ‘>’ token
set<Node&> visited_nodes;
Thanks
c++ oop object compilation set
edited Nov 11 '18 at 22:35
Matthieu Brucher
15.6k32140
asked Nov 11 '18 at 22:12
AERAER
11317
Please provide a Minimal, Complete, and Verifiable example. The best anyone can do right now is guess.
– chris
Nov 11 '18 at 22:14
2
I would guess you either need to#include <set>orusing std::set.
– aschepler
Nov 11 '18 at 22:39
@aschleper, set library already included before i post the question. Thanks
– AER
Nov 11 '18 at 22:42
add a comment |
-1
-1
-1
I receive this error that makes it difficult for me to continue coding, because I tried and tried to solve it and was unable to understand what the error means (I looked at similar questions in Stackoverflow).
I do not understand why, if I declare a set of Node objects as a type of data, I get these errors, code:
point p(p.get_x(),p.get_y());
Node a(p,0);
set<Node&> visited_nodes;
The error:
error: expected primary-expression before ‘&’ token
set<Node&> visited_nodes;
^
error: expected primary-expression before ‘>’ token
set<Node&> visited_nodes;
Thanks
c++ oop object compilation set
edited Nov 11 '18 at 22:35
Matthieu Brucher
15.6k32140
asked Nov 11 '18 at 22:12
AERAER
11317
I receive this error that makes it difficult for me to continue coding, because I tried and tried to solve it and was unable to understand what the error means (I looked at similar questions in Stackoverflow).
I do not understand why, if I declare a set of Node objects as a type of data, I get these errors, code:
point p(p.get_x(),p.get_y());
Node a(p,0);
set<Node&> visited_nodes;
The error:
error: expected primary-expression before ‘&’ token
set<Node&> visited_nodes;
^
error: expected primary-expression before ‘>’ token
set<Node&> visited_nodes;
Thanks
c++ oop object compilation set
c++ oop object compilation set
edited Nov 11 '18 at 22:35
Matthieu Brucher
15.6k32140
asked Nov 11 '18 at 22:12
AERAER
11317
edited Nov 11 '18 at 22:35
Matthieu Brucher
15.6k32140
asked Nov 11 '18 at 22:12
AERAER
11317
edited Nov 11 '18 at 22:35
Matthieu Brucher
15.6k32140
edited Nov 11 '18 at 22:35
Matthieu Brucher
15.6k32140
edited Nov 11 '18 at 22:35
Matthieu Brucher
15.6k32140
15.6k32140
asked Nov 11 '18 at 22:12
AERAER
11317
asked Nov 11 '18 at 22:12
AERAER
11317
asked Nov 11 '18 at 22:12
AERAER
11317
11317
Please provide a Minimal, Complete, and Verifiable example. The best anyone can do right now is guess.
– chris
Nov 11 '18 at 22:14
2
I would guess you either need to#include <set>orusing std::set.
– aschepler
Nov 11 '18 at 22:39
@aschleper, set library already included before i post the question. Thanks
– AER
Nov 11 '18 at 22:42
add a comment |
Please provide a Minimal, Complete, and Verifiable example. The best anyone can do right now is guess.
– chris
Nov 11 '18 at 22:14
2
I would guess you either need to#include <set>orusing std::set.
– aschepler
Nov 11 '18 at 22:39
@aschleper, set library already included before i post the question. Thanks
– AER
Nov 11 '18 at 22:42
Please provide a Minimal, Complete, and Verifiable example. The best anyone can do right now is guess.
– chris
Nov 11 '18 at 22:14
Please provide a Minimal, Complete, and Verifiable example. The best anyone can do right now is guess.
– chris
Nov 11 '18 at 22:14
2
2
I would guess you either need to
#include <set> or using std::set.– aschepler
Nov 11 '18 at 22:39
I would guess you either need to
#include <set> or using std::set.– aschepler
Nov 11 '18 at 22:39
@aschleper, set library already included before i post the question. Thanks
– AER
Nov 11 '18 at 22:42
@aschleper, set library already included before i post the question. Thanks
– AER
Nov 11 '18 at 22:42
add a comment |
1 Answer
1
active
oldest
votes
1
You cannot store references at containers. You should store pointers or the objects.
EDIT:
After chat session, we discovered the cause.
He was having a name conflict due to using namespace std;.
So I proposed:
std::set<Node> visited_nodes;
And the error dissapeared.
answered Nov 11 '18 at 22:14
LuisGPLuisGP
371110
2
While true, the question is about a syntax error.
– chris
Nov 11 '18 at 22:15
2
The error is related. As std::set is a templated class, I think the most clearer way to resolve his problem is to advice him that he cannot store references. More details can be confusing.
– LuisGP
Nov 11 '18 at 22:34
3
I don't see how the error is related at all. It's perfectly legal syntax to pass a reference as a template argument and the compiler is getting hung up on parsing. The only reason this is a problem is due to specific requirements onstd::set(and other standard containers) about which types they support.
– chris
Nov 11 '18 at 22:38
@LuisGP When i change it to that : set<Node> visited_nodes; , i get this error: expected primary-expression before ‘>’ token
– AER
Nov 11 '18 at 22:38
@AER then probably @aschepler is right. Did you includedsetorusing std::set?
– LuisGP
Nov 11 '18 at 22:40
|
show 5 more comments
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
1
You cannot store references at containers. You should store pointers or the objects.
EDIT:
After chat session, we discovered the cause.
He was having a name conflict due to using namespace std;.
So I proposed:
std::set<Node> visited_nodes;
And the error dissapeared.
answered Nov 11 '18 at 22:14
LuisGPLuisGP
371110
2
While true, the question is about a syntax error.
– chris
Nov 11 '18 at 22:15
2
The error is related. As std::set is a templated class, I think the most clearer way to resolve his problem is to advice him that he cannot store references. More details can be confusing.
– LuisGP
Nov 11 '18 at 22:34
3
I don't see how the error is related at all. It's perfectly legal syntax to pass a reference as a template argument and the compiler is getting hung up on parsing. The only reason this is a problem is due to specific requirements onstd::set(and other standard containers) about which types they support.
– chris
Nov 11 '18 at 22:38
@LuisGP When i change it to that : set<Node> visited_nodes; , i get this error: expected primary-expression before ‘>’ token
– AER
Nov 11 '18 at 22:38
@AER then probably @aschepler is right. Did you includedsetorusing std::set?
– LuisGP
Nov 11 '18 at 22:40
|
show 5 more comments
1
You cannot store references at containers. You should store pointers or the objects.
EDIT:
After chat session, we discovered the cause.
He was having a name conflict due to using namespace std;.
So I proposed:
std::set<Node> visited_nodes;
And the error dissapeared.
answered Nov 11 '18 at 22:14
LuisGPLuisGP
371110
2
While true, the question is about a syntax error.
– chris
Nov 11 '18 at 22:15
2
The error is related. As std::set is a templated class, I think the most clearer way to resolve his problem is to advice him that he cannot store references. More details can be confusing.
– LuisGP
Nov 11 '18 at 22:34
3
I don't see how the error is related at all. It's perfectly legal syntax to pass a reference as a template argument and the compiler is getting hung up on parsing. The only reason this is a problem is due to specific requirements onstd::set(and other standard containers) about which types they support.
– chris
Nov 11 '18 at 22:38
@LuisGP When i change it to that : set<Node> visited_nodes; , i get this error: expected primary-expression before ‘>’ token
– AER
Nov 11 '18 at 22:38
@AER then probably @aschepler is right. Did you includedsetorusing std::set?
– LuisGP
Nov 11 '18 at 22:40
|
show 5 more comments
1
1
1
You cannot store references at containers. You should store pointers or the objects.
EDIT:
After chat session, we discovered the cause.
He was having a name conflict due to using namespace std;.
So I proposed:
std::set<Node> visited_nodes;
And the error dissapeared.
answered Nov 11 '18 at 22:14
LuisGPLuisGP
371110
You cannot store references at containers. You should store pointers or the objects.
EDIT:
After chat session, we discovered the cause.
He was having a name conflict due to using namespace std;.
So I proposed:
std::set<Node> visited_nodes;
And the error dissapeared.
answered Nov 11 '18 at 22:14
LuisGPLuisGP
371110
edited Nov 11 '18 at 23:08
answered Nov 11 '18 at 22:14
LuisGPLuisGP
371110
answered Nov 11 '18 at 22:14
LuisGPLuisGP
371110
answered Nov 11 '18 at 22:14
LuisGPLuisGP
371110
371110
2
While true, the question is about a syntax error.
– chris
Nov 11 '18 at 22:15
2
The error is related. As std::set is a templated class, I think the most clearer way to resolve his problem is to advice him that he cannot store references. More details can be confusing.
– LuisGP
Nov 11 '18 at 22:34
3
I don't see how the error is related at all. It's perfectly legal syntax to pass a reference as a template argument and the compiler is getting hung up on parsing. The only reason this is a problem is due to specific requirements onstd::set(and other standard containers) about which types they support.
– chris
Nov 11 '18 at 22:38
@LuisGP When i change it to that : set<Node> visited_nodes; , i get this error: expected primary-expression before ‘>’ token
– AER
Nov 11 '18 at 22:38
@AER then probably @aschepler is right. Did you includedsetorusing std::set?
– LuisGP
Nov 11 '18 at 22:40
|
show 5 more comments
2
While true, the question is about a syntax error.
– chris
Nov 11 '18 at 22:15
2
The error is related. As std::set is a templated class, I think the most clearer way to resolve his problem is to advice him that he cannot store references. More details can be confusing.
– LuisGP
Nov 11 '18 at 22:34
3
I don't see how the error is related at all. It's perfectly legal syntax to pass a reference as a template argument and the compiler is getting hung up on parsing. The only reason this is a problem is due to specific requirements onstd::set(and other standard containers) about which types they support.
– chris
Nov 11 '18 at 22:38
@LuisGP When i change it to that : set<Node> visited_nodes; , i get this error: expected primary-expression before ‘>’ token
– AER
Nov 11 '18 at 22:38
@AER then probably @aschepler is right. Did you includedsetorusing std::set?
– LuisGP
Nov 11 '18 at 22:40
2
2
While true, the question is about a syntax error.
– chris
Nov 11 '18 at 22:15
While true, the question is about a syntax error.
– chris
Nov 11 '18 at 22:15
2
2
The error is related. As std::set is a templated class, I think the most clearer way to resolve his problem is to advice him that he cannot store references. More details can be confusing.
– LuisGP
Nov 11 '18 at 22:34
The error is related. As std::set is a templated class, I think the most clearer way to resolve his problem is to advice him that he cannot store references. More details can be confusing.
– LuisGP
Nov 11 '18 at 22:34
3
3
I don't see how the error is related at all. It's perfectly legal syntax to pass a reference as a template argument and the compiler is getting hung up on parsing. The only reason this is a problem is due to specific requirements on
std::set (and other standard containers) about which types they support.– chris
Nov 11 '18 at 22:38
I don't see how the error is related at all. It's perfectly legal syntax to pass a reference as a template argument and the compiler is getting hung up on parsing. The only reason this is a problem is due to specific requirements on
std::set (and other standard containers) about which types they support.– chris
Nov 11 '18 at 22:38
@LuisGP When i change it to that : set<Node> visited_nodes; , i get this error: expected primary-expression before ‘>’ token
– AER
Nov 11 '18 at 22:38
@LuisGP When i change it to that : set<Node> visited_nodes; , i get this error: expected primary-expression before ‘>’ token
– AER
Nov 11 '18 at 22:38
@AER then probably @aschepler is right. Did you included
set or using std::set?– LuisGP
Nov 11 '18 at 22:40
@AER then probably @aschepler is right. Did you included
set or using std::set?– LuisGP
Nov 11 '18 at 22:40
|
show 5 more comments
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Please provide a Minimal, Complete, and Verifiable example. The best anyone can do right now is guess.
– chris
Nov 11 '18 at 22:14
2
I would guess you either need to
#include <set>orusing std::set.– aschepler
Nov 11 '18 at 22:39
@aschleper, set library already included before i post the question. Thanks
– AER
Nov 11 '18 at 22:42