const auto it = MyVerySpecialFoosMap.find();

if(it != MyVerySpecialFoosMap)
{
  <...>
};

if(!it.is_at_the_end())
{
  <...>
};

__>if(!it.is_at_the_end())
__>{
__>  <...>
__>};
__>

if(auto x = find_value(some_map, value))
{
}

find_value(some_map, value, [](auto &x)
{
});

__>const auto it = MyVerySpecialFoosMap.find();

__>if(it != MyVerySpecialFoosMap)
__>{
__>  <...>
__>};
__>

__>if(!it.is_at_the_end())
__>{
__>  <...>
__>};
__>

auto Find(const auto& oWhere, const auto& rWhat)
{
    return {oWhere.find(rWhat), oWhere.end()};
}

int main()
{
    std::map<std::string, int> oMap = { {"a", 1}, {"b", 2} };
    
    if ( const auto [it, itEnd] = Find(oMap, "a")); it != itEnd )
    {
    
    }
    return 0;
}

 const auto& c = myVeryLongContainerName;
 auto it = c.find(...)
 if (it != c.end())
 {
  ...
 }

template<class I>
auto ptr_from_iter(I i, I e) { return i == e ? nullptr : &*i; }

template<class I, class V>
auto find_from_to(I b, I e, V&& v) { return ptr_from_iter(std::find(b, e, v), e); }

// для контейнеров, у которых есть член find
template<class C, class V>
auto find_in(C&& c, V&& v) { return ptr_from_iter(c.find(v), end(c)); }

// для контейнеров, у которых find внешний
template<class C, class V>
auto find_over(C&& c, V&& v) { return find_from_to(begin(c), end(c), v); }

int main() {
  std::map<int,string> the_map = { {1,"hello"} };
  std::vector<int> the_vec = {3,5,1};

  for (int i=0; i<2; ++i) {
    std::cout << "looking for " << i << ":" << std::endl;
    if(auto p = find_in(the_map, i)) {
      std::cout << p->first << ":" << p->second << std::endl;
    } else {
      std::cout << "not found" << std::endl;
    }

    if(auto p = find_over(the_vec, i)) {
      std::cout << *p << std::endl;
    } else {
      std::cout << "not found" << std::endl;
    }
  }
}