Re: remove_if with a mask
On 6/8/2010 11:43 AM, eLVa wrote:
[..] I tried :
template<class Z> struct maskChecker {
public:
maskChecker(const vector<bool> &mask) : it(mask.begin()) {}
bool operator()(Z&) const { return *it ++; }
private:
vector<bool>::const_iterator⁢
};
template<class T> template<class Z>
void Selector<T>::compact(vector<Z> &data, const vector<bool> &mask) {
if (data.size() != mask.size()) throw UnmatchedSize(data.size(),
mask.size());
typename vector<Z>::iterator end = remove_if(data.begin(),
data.end(), maskChecker<Z>(mask));
data.erase(end, data.end());
}
This does not compile ...
I know this is about it being initialized by a temporary variable
returned by mask.begin() ..
Should I directly pass a reference to the iterator to the constructor
of maskChecker rather than the vector itself ?
Yes, the iterator has to be created outside (next to the call to
'remove_if'), and it needs to be an lvalue. Only then you can
initialize a ref to non-const with it.
V
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