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Comment by chongli | Hacker News Reader

thus the closest the left hand is to 1, the better the chances are you'll succeed

If that is the case, then shouldn't money and connections come right after idea? Tons and tons of ideas people have every day are abandoned immediately for lack of money and connections.

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He's saying the left hand side of the equation. The order of the items on the right hand side does not matter.

Can an interpreter shirt curcuit a multiplication if the left side is 0? In Python, for instance, is the following:

    a * b * c * d

computed like this?:

    ((a * b) * c) * d

Or is it computed like this?:

    a * ((b * c) * d)

If the former is the case, then the chongli optimization could help, right?

If you have IEEE compliant floats, you can't, because the right side may result in Infinity, making the complete product NaN.

Interesting.

We're talking integers here, though (re: Python).

Short circuiting means branching, which is likely to be slower than running operators that you know to result is zero.

No, an interpreter cannot short-circuit a zero multiplication. This is because the expressions could be functions that raise exceptions.

e.g. 0 * (0/0)

e.g. f() * raise_some_exception()

Ah, of course. In hindsight, I now feel pretty silly even asking that.

The order doesn't matter :)

It doesn't matter mathematically but it does matter in real life. In real life you don't have all of the terms of the equation simultaneously, you acquire them in order. People generally have money and/or connections before they have a startup idea. Obviously, they also have an idea before they have a team, execution, or a product.

Sure, it does matter in real life, but since it probably varies from project to project I wouldn't go that far setting a "correct" order.

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