For example with this:

namespace foo {
void layerFromString(){}
int layerLimit;
class Layer {};
int localAreaYellowErrorResponse;
}

Then try to write "foo::Layer" somewhere and it keeps the active selection on layerFromString, but better match would be the Layer class since the user also started with capital letter. Maybe it could try to scan the list for options that match the input better.

Also it would make a lot of sense to highlight (or sort the list to) the closest match. For example:

QList<int> list;

And then trying to write list.front suggests emplaceFront as the first option. Oddly enough it does suggest front if only list.fr is written.