Re: lambda : capturing a data member - is it legal?
On Sat, 19 Feb 2011 06:59:15 -0600, Daniel Kr?gler wrote:
Am 18.02.2011 13:51, schrieb Helmut Jarausch:
Hi,
reading Scott Meyers' "Overview of the New C++" I stumbled over
#include<algorithm>
#include<list>
class Widget {
public:
void doSomething();
private:
std::list<int> li;
int minVal;
};
void Widget::doSomething() {
auto it = std::find_if(li.cbegin(), li.cend(),
[minVal](int i) { return i> minVal; } // error?
);
}
Scott says, that the second to last line is in error and 'repairs' it
by capturing 'this' instead of minVal.
On the other hand, gcc-4.5.2 accepts the code above.
Thanks Daniel, thanks Johannes.
Sorry, but I still haven't understood why the rules for capturing by
value are so strict. What problems could occur if one would allow this.
If I called the constructor for an object of a some class I could have
used the value of minVal.
Helmut.
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