Method acquire

src/fl/audio/fft/fft.cpp.hpp:20–33

class FloatVectorPool {
  public:
    fl::vector<float> acquire(fl::size capacity) {
        for (fl::size i = 0; i < mPool.size(); ++i) {
            if (mPool[i].capacity() >= capacity) {
                fl::vector<float> v = fl::move(mPool[i]);
                mPool[i] = fl::move(mPool.back());
                mPool.pop_back();
                v.clear();
                return v;
            }
        }
        fl::vector<float> v;
        v.reserve(capacity);
        return v;
    }

    void release(fl::vector<float>&& v) {
        if (v.capacity() > 0 && mPool.size() < kMaxPoolSize) {