Can my technology company use only Swift?

Using Swift
22

Take this simple C++ ring buffer implementation:

#define count 10*512

class CRingBuffer {
    float samples[count];
    int readPos = 0;
    int writePos = 0;
    
    void put(float sample) {
        samples[writePos++ % count] = sample;
    }
    float get() {
        return samples[readPos++ % count];
    }
};

If you naïvely convert it to swift:

class RingBuffer {
    static let count = 10*512
    var buffer: [Float]
    var writePos = 0
    var readPos = 0
    
    init() {
        buffer = [Float](repeating: 0, count: Self.count)
    }
    func put(_ v: Float) {
        buffer[writePos % Self.count] = v
        writePos += 1
    }
    func get() -> Float {
        let v = buffer[readPos % Self.count]
        readPos += 1
        return v
    }
}

you will have an implementation which has retain/release in its get/put methods (which can take a mutex lock) -- not good for use in real time code: see old but good links: link1 (49:12 -- 50:50), link2 and link3. That's the kind of minefields I am talking about. If you are extra careful (switch to unsafe pointers and verify the resulting asm (which can change from one swift version to another)) - yes, you can link4 (29:00 -- 32:40, 37:50 -- 42:25).

Relevant thread from the past.

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