src/Zipkin/Tracer.php
public function getCurrentSpan(): ?Span
    {
        $currentContext = $this->currentTraceContext->getContext();
        return $currentContext === null ? null : $this->toSpan($currentContext);
    }
public function getCurrentSpan(): ?Span
    {
        $currentContext = $this->currentTraceContext->getContext();
        return $currentContext === null ? null : $this->toSpan($currentContext);
    }
Returns the current span in scope or null if there isn't one.

@return Span|null