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    <p>Start by avoiding pointers.</p> <p>Use them when:</p> <ul> <li>You want to use the <a href="http://en.wikipedia.org/wiki/Opaque_pointer" rel="noreferrer">Pimpl idiom</a>, or an <a href="http://en.wikipedia.org/wiki/Abstract_factory_pattern" rel="noreferrer">abstract factory</a>.</li> <li>The <code>Bar</code> instance is actually managed by some other part of your program, whereas the <code>Foo</code> class just needs to be able to access it.</li> <li>You want to postpone the construction of the <code>Bar</code> object (i.e., you want to create it <em>after</em> constructing <code>Foo</code>).</li> <li>In your business logic, the <code>Bar</code> object may not exist at all; you would use <code>null</code> also in Java. However, check out <a href="http://www.boost.org/doc/libs/1_37_0/libs/optional/doc/html/index.html" rel="noreferrer">boost::optional</a> as well.</li> <li><code>Bar</code> is actually a base class, and you need the instance to be polymorphic.</li> <li>You happen to be using a toolkit that prefers to present GUI widgets as pointers. Examples could include (but are certainly not limited to) <a href="http://www.wxwidgets.org/" rel="noreferrer">wxWidgets</a> and <a href="http://www.cs.unc.edu/~rademach/glui/" rel="noreferrer">GLUI</a>.</li> </ul> <p>In any of these cases (*), start by using a smart pointer, such as <a href="http://www.boost.org/doc/libs/release/libs/smart_ptr/shared_ptr.htm" rel="noreferrer">boost::shared_ptr</a>. Otherwise, you are likely to forget to deallocate the memory, sooner or later. Once you know what you are doing, consider case-by-case what pointer type is best.</p> <p>(*) any case – except, probably, the bullet regarding GUI widgets; in this case, your toolkit would most probably manage the resources for you as well</p>
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    1. POWhen to use pointers and when not to?
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    1. CO...or in the case you're writing a toolkit (which is often my case). I have never had problems with pointers which smart pointers would solve, so I wouldn't say "USE THEM!" but "it is easiest to use them in most cases."
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    2. CO@strager: True. Softened the remark a bit.
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    3. COmaybe i'm alone. but i think especially beginners should (not in real world projects of course) first try to work with raw pointers. i think this is similar to the question "IDE/no IDE". they should learn to know *why* smart pointers are useful and what pitfalls they avoid
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      1. USJohannes Schaub - litb
 

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