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.send { color:#77bb77; }
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.error { color:#AA0000; }</style></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;"><div class="bloop_markdown"><p>I’ve got one more questions about <code>Unsafe(Mutable)Pointer</code>. I know that I’m able to access memory that might not belong to me. </p>
<p>My question is:</p>
<ul>
<li><p>Can I trust these functions that they will return a pointer to some memory when I allocate more than one object AND when I’m moving only inside that range?</p>
<pre><code class="swift">public func successor() -> UnsafeMutablePointer<Memory>
public func predecessor() -> UnsafeMutablePointer<Memory>
public func advancedBy(n: Int) -> UnsafeMutablePointer<Memory>
</code></pre></li>
<li><p><code>UnsafeMutablePointer<Int>.alloc(4)</code> when I advance only in range of <code>[0,1,2,3]</code> am I safe or could I get a pointer to memory that does not belong to me?</p></li>
<li><p>Example:</p>
<pre><code class="swift">// imagine this is some memory portion,
// where x is memory that does not belong to me
// and 0 is moemory free to use
[…, x, 0, 0, 0 x, 0, x, …]
// now I want to allocate 4 objects
// variant A:
[…, x, MY1, MY2, MY3, x, MY4, x, …]
// my pointer will sit at `MY1` and if I advance by 2 I'll get `x`
// can this happen to me?
// variant B:
// Unsafe(Mutable)Pointer will ensure that I always get memory tied together
// (or the above functions will skip memory that doesn't belong to me??):
[…, x, MY1, MY2, MY3, MY4 x, …]
</code></pre></li>
</ul>
<p>So which is right?</p>
<p></p></div><div class="bloop_original_html"><style>body{font-family:Helvetica,Arial;font-size:13px}</style><div id="bloop_customfont" style="font-family:Helvetica,Arial;font-size:13px; color: rgba(0,0,0,1.0); margin: 0px; line-height: auto;"><br></div><br><div id="bloop_sign_1464280737664475904" class="bloop_sign"><div style="font-family:helvetica,arial;font-size:13px">-- <br>Adrian Zubarev<br>Sent with Airmail</div></div></div><div class="bloop_markdown"><p></p></div></body></html>