How to iterate over concurrent_hash_map using accessor?

[sunholee0127]

Hi

The concurrent operations (count, find, insert, and erase) invalidate any iterators pointing into the affected instance. It is unsafe to use these operations concurrently with any other operation.

so, I want to iterate and erase elements over concurrent_hash_map using accessor (not using iterator)

How can i do that?

[bash]Hash::accessor acc;
for(Hash::iterator iter = map.begin(); iter != map.end() ; ++iter)
{
  map.find(acc, iter->first);
  if( ~~)
  {
     map.erase(acc);
  }
}[/bash]

is that a thread safe?

I wonder that erasing elements invalidate the iterator.

Thanks.

[RafSchietekat]

If erasing relatively few elements, store relevant keys into a vector, then revisit the map to erase the corresponding elements. If erasing most elements, copy selectively to new map and swap.