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    <blockquote> <p>is <code>return;</code> the same as <code>return NULL;</code> in C++?</p> </blockquote> <p>No.</p> <p><code>return</code> is used to "break" out from a function that has no return value, i.e. a return type of <code>void</code>.</p> <p><code>return NULL</code> returns the value <code>NULL</code>, and the return type of the function it's found in must be compatible with <code>NULL</code>.</p> <hr> <blockquote> <p>I understand that in C++, <code>return NULL;</code> is the same as <code>return 0;</code> in the context of pointers.</p> </blockquote> <p>Sort of. <code>NULL</code> may not be equivalent to <code>0</code>, but it will at least convert to something that is.</p> <hr> <blockquote> <p>Obviously for integers, this is not the case as NULL cannot be added, subtracted, etc.</p> </blockquote> <p>You can perform addition and subtraction to pointers just fine. However, <code>NULL</code> must have integral type (4.10/1 and 18.1/4 in C++03) anyway so it's moot. <code>NULL</code> may very well be a macro that expands to <code>0</code> or <code>0UL</code>.</p> <p>Some modern compilers will at least warn you if it was actually <code>NULL</code> you wrote, though.</p> <hr> <blockquote> <p>And that it is encouraged by some to use 0 instead of NULL for pointers because it is more convenient for portability. I'm curious if this is another instance where an equivalence occurs.</p> </blockquote> <p>No. And I disagree with this advice. Though I can see where it's coming from, since <code>NULL</code>'s exact definition varies across implementations, using <code>NULL</code> will make it <em>much</em> easier to replace with <code>nullptr</code> when you switch to C++11, and if nothing else is self-documenting.</p>
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    1. POIn C++, is "return;" the same thing as "return NULL;"?
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    1. POIn C++, is "return;" the same thing as "return NULL;"?
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    1. CO+1 The advice to use `0` instead of `NULL` [comes from Stroustroup](http://www.stroustrup.com/bs_faq2.html#null), but that's not all he said about the issue: he also mentioned using `nullptr` in C++11 :)
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    2. COThank you for the comprehensive breakdown. I apologize as I had much confused, but your answer really cleared up a lot of things.
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    3. CO@dasblinkenlight: Not everything Stroustroup says must be correct! Don't forget he's responsible for C++ in the first place :P
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