How to call a member function on a parameter with std::for_each and boost::bind?

Question

I want to add a series of strings to a combo box using std::for_each. The objects are of type Category and I need to call GetName on them. How can I achieve this with boost::bind?

const std::vector<Category> &categories = /**/;
std::for_each(categories.begin(), categories.end(), boost::bind(&CComboBox::AddString, &comboBox, _1);

The current code fails as it's trying to call CComboBox::AddString(category). Which is obviously wrong. How can I call CComboBox::AddString(category.GetName()) using the current syntax?

Is there a strict necessity of using `std::foreach` instead of iterating? — baton, Sep 21 '10 at 12:19

score 8 · Accepted Answer · answered Sep 21 '10 at 12:34

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std::for_each(categories.begin(), categories.end(), boost::bind(&CComboBox::AddString, &comboBox, boost::bind(&Category::GetName, _1)));

answered Sep 21 '10 at 12:34

baton

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Andreas Magnusson · Answer 2 · 2010-09-21T13:33:51.497

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You can use lambdas, either Boost.Lambda or C++ lambdas (if your compiler supports them):

// C++ lambda
const std::vector<Category> &categories = /**/;
std::for_each(categories.begin(), categories.end(),
              [&comboBox](const Category &c) {comboBox.AddString(c.GetName());});

edited Sep 21 '10 at 13:33

answered Sep 21 '10 at 12:41

Andreas Magnusson

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Thanks for those suggestions, VS2008 doesn't support lambdas though (I guess I should have specified that in the tags). – Mark Ingram Sep 21 '10 at 12:58
VS2008 supports Boost.Lambda. – Andreas Magnusson Sep 21 '10 at 13:14
Anyway, I removed the Boost.Lambda example since it was incorrect and a correct one would look more like the accepted answer. – Andreas Magnusson Sep 21 '10 at 13:35

Gustavo Muenz · Answer 3 · 2011-06-30T17:04:13.910

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I know you asked about using std::for_each, but in those cases I like using BOOST_FOREACH instead, it makes the code more readable (in my opinion) and easier to debug:

const std::vector<Category> &categories = /**/;
BOOST_FOREACH(const Category& category, categories)
    comboBox.AddString(category.GetName());

edited Jun 30 '11 at 17:04

answered Sep 21 '10 at 13:35

Gustavo Muenz

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+1 from me. BOOST_FOREACH is an incredibly cool feat. The inventor Eric Niebler wrote an article describing it: http://www.artima.com/cppsource/foreach.html. Minor nitpick, if you use braces it becomes more clear how incredibly cool BOOST_FOREACH is. – Andreas Magnusson Sep 22 '10 at 06:58

score 0 · Answer 4 · answered Sep 21 '10 at 12:49

0

A possible way to achieve this would be using mem_fun and bind1st

answered Sep 21 '10 at 12:49

mukeshkumar

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How to call a member function on a parameter with std::for_each and boost::bind?

4 Answers4