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diff --git a/devdocs/c/language%2Fnullptr.html b/devdocs/c/language%2Fnullptr.html deleted file mode 100644 index 9c5d8a87..00000000 --- a/devdocs/c/language%2Fnullptr.html +++ /dev/null @@ -1,59 +0,0 @@ - <h1 id="firstHeading" class="firstHeading">Predefined null pointer constant <span class="t-mark-rev t-since-c23">(since C23)</span> -</h1> <h3 id="Syntax"> Syntax</h3> <table class="t-sdsc-begin"> <tr class="t-sdsc"> <td> <code>nullptr</code> </td> <td class="t-sdsc-nopad"> </td> <td> <span class="t-mark-rev t-since-c23">(since C23)</span> </td> -</tr> -</table> <h3 id="Explanation"> Explanation</h3> <p>The keyword <code>nullptr</code> denotes a predefined null pointer constant. It is a <a href="value_category#Non-lvalue_object_expressions" title="c/language/value category">non-lvalue</a> of type <code><a href="../types/nullptr_t" title="c/types/nullptr t">nullptr_t</a></code>. <code>nullptr</code> can be <a href="conversion" title="c/language/conversion">converted</a> to a pointer types or <code>bool</code>, where the result is the null pointer value of that type or <code>false</code> respectively.</p> -<h3 id="Keywords"> Keywords</h3> <p><a href="../keyword/nullptr" title="c/keyword/nullptr"><code>nullptr</code></a></p> -<h3 id="Example"> Example</h3> <div class="t-example"> -<p>Demonstrates that a copy of <code>nullptr</code> can also be used as a null pointer constant.</p> -<div class="c source-c"><pre data-language="c">#include <stddef.h> -#include <stdio.h> - -void g(int*) -{ - puts("Function g called"); -} - -#define DETECT_NULL_POINTER_CONSTANT(e) \ - _Generic(e, \ - void* : puts("void*"), \ - nullptr_t : puts("nullptr_t"), \ - default : puts("integer") \ - ) - -int main() -{ - g(nullptr); // OK - g(NULL); // OK - g(0); // OK - - auto cloned_nullptr = nullptr; - g(cloned_nullptr); // OK - - [[maybe_unused]] auto cloned_NULL = NULL; -// g(cloned_NULL); // implementation-defined: maybe OK - - [[maybe_unused]] auto cloned_zero = 0; -// g(cloned_zero); // Error - - DETECT_NULL_POINTER_CONSTANT(((void*)0)); - DETECT_NULL_POINTER_CONSTANT(0); - DETECT_NULL_POINTER_CONSTANT(nullptr); - DETECT_NULL_POINTER_CONSTANT(NULL); // implementation-defined -}</pre></div> <p>Possible output:</p> -<div class="text source-text"><pre data-language="c">Function g called -Function g called -Function g called -Function g called -void* -integer -nullptr_t -void*</pre></div> </div> <h3 id="See_also"> See also</h3> <table class="t-dsc-begin"> <tr class="t-dsc"> <td> <div><a href="../types/null" title="c/types/NULL"> <span class="t-lines"><span>NULL</span></span></a></div> </td> <td> implementation-defined null pointer constant <br> <span class="t-mark">(macro constant)</span> </td> -</tr> <tr class="t-dsc"> <td> <div><a href="../types/nullptr_t" title="c/types/nullptr t"> <span class="t-lines"><span>nullptr_t</span></span></a></div> -<div><span class="t-lines"><span><span class="t-mark-rev t-since-c23">(C23)</span></span></span></div> </td> <td> the type of the predefined null pointer constant <strong class="selflink"><code>nullptr</code></strong> <br> <span class="t-mark">(typedef)</span> </td> -</tr> <tr class="t-dsc"> <td colspan="2"> <span><a href="https://en.cppreference.com/w/cpp/language/nullptr" title="cpp/language/nullptr">C++ documentation</a></span> for <code>nullptr</code> </td> -</tr> </table> <div class="_attribution"> - <p class="_attribution-p"> - © cppreference.com<br>Licensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.<br> - <a href="https://en.cppreference.com/w/c/language/nullptr" class="_attribution-link">https://en.cppreference.com/w/c/language/nullptr</a> - </p> -</div> |