How to get the BPM since getCurrentPosition is deprecated?

I’m trying to write a delay plugin so I need to get the bpm.

However I have no idea how to use juce::AudioPlayHead::PositionInfo::getBpm()

I get this error

../../Source/PluginProcessor.cpp:199:23: error: ‘positionInfo’ was not declared in this scope
  199 |     auto currentBpm = positionInfo->getBpm();
         | 

with the declaration in the .h

  juce::AudioPlayHead::PositionInfo* positionInfo;

and in the .cpp

    auto currentBpm = positionInfo->getBpm();

I’ve tried other configurations but nothing works. Just wondering how to get the bpm so I can set timed delays

in the processBlock()

void MyPluginAudioProcessor::processBlock (juce::AudioBuffer<float>& buffer, juce::MidiBuffer& midiMessages)
{
    double bpm { 120 }; // default fallback when host does not provide info
    if (auto bpmFromHost = *getPlayHead()->getPosition()->getBpm())
        bpm = bpmFromHost;
}

EDIT:
yes, it was actually way simpler than i thought it would be.

Thanks @hugoderwolf for pointing it out.

You can omit inheriting AudioPlayHead, it does nothing in the code example.

Also, since the PositionInfo is an Optional, the code in processBlock() should check if there is a value, and act accordingly.

For example, I think in a Standalone build, you don’t get a positionInfo. In AudioPluginHost on the other hand, you get a positionInfo, but the BPM is 0, which is also a failure mode you might want to address. In these cases, going with a default like 120 BPM or switching off any tempo syncing would make sense.