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Comment by br121 | Hacker News Reader

It doesn't convert bogosort into heapsort either, despite the second being much faster than the first. I'm guessing that it's not that easy going from one to the other because the only thing they have in common is the output (and only after you have checked the last value), so if the transformation is not hard-coded into the compiler, the odds of it randomly discovering the optimization is close to zero

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Yeah, I would expect such transformations to be implemented as optimizations. Just like maybe (the admitedly simpler):

    (+ ((lambda () 1)) ((lambda () 1))) -> (+ 1 1)

A syntactical transformation, where it is possible as an equivalent transformation.

I may be overlooking special cases, but I thought the compiler is smart enough to infer that the array elements are integers and that `<` will result in a boolean, which is just `0` and `1` and will understand that having only the `if` without `else` branch is equivalent in this case. Guess I was wrong and the compiler is not sophisticated in this specific way.

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