U++ forum: Welcome to the forum

Search on this site

Search in forums

Home » U++ Library support » U++ Core » VectorMap.Get (Problem fetching value of vectormap second time)

Show: Today's Messages :: Show Polls :: Message Navigator
E-mail to friend

VectorMap.Get [message #45231]

Tue, 13 October 2015 14:31

deep
Messages: 268
Registered: July 2011
Location: Bangalore

Experienced Member

Hi,

When I want to get the content of VecotorMap second time I am getting Assert Failed error.

#include <Core/Core.h>

using namespace Upp;

CONSOLE_APP_MAIN
{
	Vector<int> v1;
	VectorMap<String,Vector<int>> Vm ;
	
	v1.Clear();
	v1.Add(0);
	v1.Add(3);
	Vm.Add("key1",v1);

	v1.Clear();
	v1.Add(10);
	v1.Add(31);
	v1.Add(41);
	Vm.Add("key2",v1);
	
	Vector<int> v2 ;
	v2 = Vm.Get("key1");
	DUMP(v2);

	v2.Clear();
	v2 = Vm.Get("key2");
	DUMP(v2);
	
	v2.Clear();
	v2 = Vm.Get("key1");
	DUMP(v2);
}

Log content

v2 = [0, 3]
v2 = [10, 31, 41]
v2 = ****************** ASSERT FAILED: Assertion failed in c:\devtools\upp_git\uppsrc\core\Vcont.h, line 34
Broken rval_ semantics

It is working whith VectorMap<String,String>

#include <Core/Core.h>

using namespace Upp;

CONSOLE_APP_MAIN
{
	VectorMap<String,String> v1;
	
	v1.Add("key1","val1");
	v1.Add("key2","val2");
	v1.Add("key3","val3");
	
	String s;
	
	s.Clear();
	s= v1.Get("key1");
	DUMP(s);
	
	s.Clear();
	s= v1.Get("key2");
	DUMP(s);
	
	s.Clear();
	s= v1.Get("key3");
	DUMP(s);
	
	s.Clear();
	s= v1.Get("key1");
	DUMP(s);
}

Log content

s = val1
s = val2
s = val3
s = val1

Warm Regards

Deepak

[Updated on: Tue, 13 October 2015 14:42]

Report message to a moderator

Re: VectorMap.Get [message #45232 is a reply to message #45231]

Tue, 13 October 2015 16:38

Klugier
Messages: 1099
Registered: September 2012
Location: Poland, Kraków

Senior Contributor

Hello Deep,

Try to clone your vector. I think in your case there is move operation for some reason. Maybe someone that knows better that mechanism can describe it for you. On the other hand I have got compilation error of your example in the latest upp. Code that should work:

#include <Core/Core.h>

using namespace Upp;

CONSOLE_APP_MAIN
{
	Vector<int> v1;
	VectorMap<String, Vector<int>> Vm;
	
	v1.Clear();
	v1.Add(0);
	v1.Add(3);
	Vm.Add("key1", v1); // <- Vector was copied

	v1.Clear();
	v1.Add(10);
	v1.Add(31);
	v1.Add(41);
	Vm.Add("key2", v1); // <- Vector was copied
	
	Vector<int> v2;
	v2 = clone(Vm.Get("key1")); // <- Without clone, probably move operation
	DUMP(v2);

	v2.Clear();
	v2 = clone(Vm.Get("key2"));
	DUMP(v2);
	
	v2.Clear();
	v2 = clone(Vm.Get("key1"));
	DUMP(v2);
}

Here is my log values:

v2 = [0, 3]
v2 = [10, 31, 41]
v2 = [0, 3]

------------------------------------------------------------ --
P.S.
Maybe you should put space after comma. In my opinion declaration like:

VectorMap<String, Vector<int>>

is more readable that

VectorMap<String,Vector<int>>

.

Sincerely,
Klugier

U++ - one framework to rule them all.

[Updated on: Tue, 13 October 2015 16:47]

Report message to a moderator

Re: VectorMap.Get [message #45238 is a reply to message #45232]

Thu, 15 October 2015 11:02

mirek
Messages: 14257
Registered: November 2005

Ultimate Member

[quote title=Klugier wrote on Tue, 13 October 2015 16:38]Hello Deep,

Try to clone your vector. I think in your case there is move operation for some reason. Maybe someone that knows better that mechanism can describe it for you. [code]

Yes, it is 'pick' (U++ variant of move).

In C++11 mode, the code would not even compile. Unfortunately, before c++11, there are no means to detect these errors at compile time.

Note that the optimal variant to using 'clone' is to use const reference (unless you need to change the element you are getting).