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From:   "Greg Morenz" <greg@droid.cafe>
Message-ID: <36a390c236b2f02ee2ac16208a4fc94f@droid.cafe>
Subject: Re: [PATCH 00/13] [RFC] Rust support
To:     "Leandro Coutinho" <lescoutinhovr@gmail.com>
Cc:     rust-for-linux@vger.kernel.org
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> Rust `for` works fine, until the step is not a simple unsigned int, eg:
> for (int i = n / 2; i > 0; i /= 2)
> 
> In Rust you do: (please let me know if there is a better way):
> let mut i = n / 2;
> while i > 0 {
>     // some logic ...
>     i /= 2;
> }

For this specific example, you could do

let mut i = n;
while { i /= 2; i > 0 } {
    // some logic ...
}

This works because { i /= 2; i > 0 } is a single "block" expression that first
divides i by two, and then "returns" (at the block level) i > 0. Note I have to
not pre-divide n by two when initializing i.

In general rust doesn't have an equivalent construct to C style for loops though.