search for: findandconstruct

...; // do_stuff return Value = Result; However, I'm using an enum as a map value, so when you do Map[Key] while Key is not yet in the map, the new value will be unitialized (I can't define a constructor on an enum, right?). So, to solve this, I propose adding a second version of DenseMap::FindAndConstruct, which has an extra argument for the default value. So, it would do the same thing as the original (return a reference to the value from the map, adding it if it's not already in), but instead of using ValueT() as a default value, it would use an argument. Any objections to adding this? Sugges...

...; However, I'm using an enum as a map value, so when you do Map[Key] > while Key > is not yet in the map, the new value will be unitialized (I can't > define a > constructor on an enum, right?). > > So, to solve this, I propose adding a second version of > DenseMap::FindAndConstruct, which has an extra argument for the > default value. > So, it would do the same thing as the original (return a reference > to the > value from the map, adding it if it's not already in), but instead > of using > ValueT() as a default value, it would use an argument. &g...

> Assuming the default value is not a valid entry in your map (for instance, > if you're using pointers), you can do: > > Foo& entry = DenseMap[Key] > if (entry == DefaultValue) > entry = constructNewValue(); The problem here is that the DefaultValue is undefined. However, Chris suggested that the default value, ValueT(), is not undefined but simply zero. However, on

On Fri, Jun 6, 2008 at 12:27 AM, Matthijs Kooijman <matthijs at stdin.nl> wrote: >> Assuming the default value is not a valid entry in your map (for instance, >> if you're using pointers), you can do: >> >> Foo& entry = DenseMap[Key] >> if (entry == DefaultValue) >> entry = constructNewValue(); > The problem here is that the DefaultValue