{"id":109500,"date":"2020-05-29T19:31:35","date_gmt":"2020-05-29T11:31:35","guid":{"rendered":"http:\/\/4563.org\/?p=109500"},"modified":"2020-05-29T19:31:35","modified_gmt":"2020-05-29T11:31:35","slug":"c-typedef-%e6%8c%87%e9%92%88%e5%87%bd%e6%95%b0%e9%97%ae%e9%a2%98","status":"publish","type":"post","link":"http:\/\/4563.org\/?p=109500","title":{"rendered":"[C++] typedef \u6307\u9488\u51fd\u6570\u95ee\u9898"},"content":{"rendered":"<div>\n<div>\n<div>\n<h1>                  [C++] typedef \u6307\u9488\u51fd\u6570\u95ee\u9898               <\/h1>\n<p> <\/p>\n<div>\n<div> <span>\u8cc7\u6df1\u5927\u4f6c : ligiggy <\/span>  <span><i><\/i> 1<\/span> <\/div>\n<div> <\/div>\n<\/p><\/div>\n<\/p><\/div>\n<\/p><\/div>\n<div isfirst=\"1\"> <\/p>\n<p>\u81ea\u5df1\u778e\u5199\u4e86\u4e00\u6bb5\u4ee3\u7801\uff0c\u5982\u4e0b\uff1a<\/p>\n<pre><code>typedef char* pFunc(char*);  char* func1(char * p) {  cout &lt;&lt; p &lt;&lt; endl;   return p; }  int main() {  pFunc (*c);   c = func1;   c(\"123\"); } <\/code><\/pre>\n<p>\u8fd9\u6837\u4f7f\u7528\u7684\u65f6\u5019\u662f OK \u7684\u3002<\/p>\n<p>\u4f46\u662f\u4e0d\u80fd\u8fd9\u6837\u521d\u59cb\u5316\u4e00\u4e2a\u53d8\u91cf\uff0cVC++\u7f16\u8bd1\u5668\u4f1a\u63d0\u793a\uff1a\u201c=\u201d\u4e0d\u662f\u5de6\u64cd\u4f5c\u6570<\/p>\n<pre><code> pFunc(c);  c = func1;  <\/code><\/pre>\n<p>\u4e5f\u4e0d\u80fd\u8fd9\u6837<\/p>\n<pre><code> pFunc c;  c = func1; <\/code><\/pre>\n<p>\u641c\u4e0d\u5230\u4e00\u4e2a\u6bd4\u8f83\u5408\u7406\u7684\u89e3\u91ca\uff0c\u8bf7\u5927\u4f6c\u8d50\u6559\uff01<\/p>\n<\/p><\/div>\n<p><\/p>\n<div> <b>\u5927\u4f6c\u6709\u8a71\u8aaa<\/b> (<span>22<\/span>)        <\/div>\n<div> <\/div>\n<\/p><\/div>\n<\/p><\/div>\n<ul>\n<li data-pid=\"1822916\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u8cc7\u6df1\u5927\u4f6c : loriann <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             c \u662f\u4ec0\u4e48\uff1f \u6ca1\u770b\u61c2                                                            <\/div>\n<\/p><\/div>\n<\/li>\n<li data-pid=\"1822917\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u4e3b<\/span> <span>\u8cc7\u6df1\u5927\u4f6c : ligiggy <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             @loriann c \u662f\u5b9a\u4e49\u7684\u53d8\u91cf\u540d\u554a                                                            <\/div>\n<\/p><\/div>\n<\/li>\n<li data-pid=\"1822918\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u8cc7\u6df1\u5927\u4f6c : loriann <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             c \u662f\u4ec0\u4e48\u7c7b\u578b\u7684\u53d8\u91cf\u5462?                                                            <\/div>\n<\/p><\/div>\n<\/li>\n<li data-pid=\"1822919\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u4e3b<\/span> <span>\u8cc7\u6df1\u5927\u4f6c : ligiggy <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             @loriann pFunc \u554a                                                            <\/div>\n<\/p><\/div>\n<\/li>\n<li data-pid=\"1822920\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u8cc7\u6df1\u5927\u4f6c : AlohaV2 <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             typedef \u8fd4\u56de\u503c\u7c7b\u578b (*\u51fd\u6570\u540d\u5b57)(\u53c2\u6570&#8230;)<br \/>\u5efa\u8bae\u4e3b\u65e9\u65e5\u7528\u4e0a c++11\uff0cstd::function \u597d\u7528\u4e00\u4e9b.                                                            <\/div>\n<\/p><\/div>\n<\/li>\n<li data-pid=\"1822921\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u4e3b<\/span> <span>\u8cc7\u6df1\u5927\u4f6c : ligiggy <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             @AlohaV2 \u4f60\u8fd9\u4e2a\u4e5f\u4e0d\u5bf9\u554a\uff0c\u4e0d\u662f\u51fd\u6570\u6307\u9488\u3002                                                            <\/div>\n<\/p><\/div>\n<\/li>\n<li data-pid=\"1822922\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u8cc7\u6df1\u5927\u4f6c : loriann <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             \u54ce\uff0c\u771f\u662f\u4e0a\u706b\u3002\u6000\u7591\u81ea\u5df1\u591a\u5e74 c++\u662f\u4e0d\u662f\u5582\u4e86\u72d7\u4e86\u3002\u4f60\u53ef\u4ee5\u8fd9\u6837\u7528 pFunc* c = func1                                                            <\/div>\n<\/p><\/div>\n<\/li>\n<li data-pid=\"1822923\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u4e3b<\/span> <span>\u8cc7\u6df1\u5927\u4f6c : ligiggy <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             @loriann \u5367\u69fd\u597d\u50cf\u662f\u7684\u3002\u6211\u7684 c++\u5582\u4e86\u72d7                                                            <\/div>\n<\/p><\/div>\n<\/li>\n<li data-pid=\"1822924\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u8cc7\u6df1\u5927\u4f6c : TaylorJack123 <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             \u4f60\u8fd9 typedef \u5199\u9519\u4e86\uff0c\u5e94\u8be5\u662f char* (*pFunc)(char*);                                                            <\/div>\n<\/p><\/div>\n<\/li>\n<li data-pid=\"1822925\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u8cc7\u6df1\u5927\u4f6c : soy <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             https:\/\/gist.github.com\/ZikiSoy\/394abf58cab924a4497c6755ddefeefe <button onclick=\"lazyGist(this)\">\u00a0\u663e\u793a Gist \u4ee3\u7801\u00a0<\/button> <\/div>\n<\/p><\/div>\n<\/li>\n<li data-pid=\"1822926\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u4e3b<\/span> <span>\u8cc7\u6df1\u5927\u4f6c : ligiggy <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             @TaylorJack123 \u51ed\u4ec0\u4e48\u8bf4\u6211\u5199\u9519\u4e86\uff1f                                                            <\/div>\n<\/p><\/div>\n<\/li>\n<li data-pid=\"1822927\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u4e3b<\/span> <span>\u8cc7\u6df1\u5927\u4f6c : ligiggy <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             @soy 666666666666                                                            <\/div>\n<\/p><\/div>\n<\/li>\n<li data-pid=\"1822928\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u8cc7\u6df1\u5927\u4f6c : SPACELAN <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             \u8fd8\u53ef\u4ee5\u8fd9\u6837\u5199<\/p>\n<p>char* (*c)(char*) = func1;<\/p>\n<p>\u61c2\u6211\u7684\u610f\u601d\u5427                                                            <\/p><\/div>\n<\/p><\/div>\n<\/li>\n<li data-pid=\"1822929\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u4e3b<\/span> <span>\u8cc7\u6df1\u5927\u4f6c : ligiggy <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             @SPACELAN \u61c2                                                            <\/div>\n<\/p><\/div>\n<\/li>\n<li data-pid=\"1822930\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u8cc7\u6df1\u5927\u4f6c : pright <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             \u4e3b\u8fd9\u6837\u5199\u4e5f\u6ca1\u95ee\u9898\u7684\uff0c\u4f60\u628a\u90a3\u4e2a\u62ec\u53f7\u53bb\u6389\u5c31\u597d\u7406\u89e3\u4e86\u3002<br \/>pFunc *c;                                                            <\/div>\n<\/p><\/div>\n<\/li>\n<li data-pid=\"1822931\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u8cc7\u6df1\u5927\u4f6c : pright <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             EXAMPLE 4 On the other hand, typedef names can be used to improve code readability. All three of the<br \/>following declarations of the signal function specify exactly the same type, the first without making use<br \/>of any typedef names.<br \/>typedef void fv(int), (*pfv)(int);<br \/>void (*signal(int, void (*)(int)))(int);<br \/>fv *signal(int, fv *);<br \/>pfv signal(int, pfv);                                                            <\/div>\n<\/p><\/div>\n<\/li>\n<li data-pid=\"1822932\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u8cc7\u6df1\u5927\u4f6c : pright <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             http:\/\/www.open-std.org\/jtc1\/sc22\/wg14\/www\/docs\/n1570.pdf                                                            <\/div>\n<\/p><\/div>\n<\/li>\n<li data-pid=\"1822933\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u4e3b<\/span> <span>\u8cc7\u6df1\u5927\u4f6c : ligiggy <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             @pright \u55ef\uff0c\u8c22\u8c22\u6307\u6559\u3002\u5df2\u7ecf\u609f\u5230\u4e86\u3002\u8fd9\u4e48\u4e9b\u5e74\u767d\u5b66\u4e86\uff0c\u5076\u7136\u53d1\u73b0\u81ea\u5df1\u51e0\u5e74\u524d\u5199\u7684\u535a\u5ba2\uff0c\u7adf\u7136\u770b\u4e0d\u61c2\u4e86\u3002                                                            <\/div>\n<\/p><\/div>\n<\/li>\n<li data-pid=\"1822934\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u8cc7\u6df1\u5927\u4f6c : ashong <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             typedef \u683c\u5f0f\u4e0d\u5bf9<\/p>\n<p>&#8220;`<br \/>typedef char* (*pFunc)(char*);<\/p>\n<p>char* func1(char * p)<br \/>{<br \/> std::cout &lt;&lt; p &lt;&lt; std::endl;<\/p>\n<p> return p;<br \/>}<\/p>\n<p>int main()<br \/>{<br \/> pFunc c;<\/p>\n<p> c = func1;<\/p>\n<p> c(&#8220;123&#8221;);<\/p>\n<p> return 0;<br \/>}<br \/>&#8220;`                                                            <\/div>\n<\/p><\/div>\n<\/li>\n<li data-pid=\"1822935\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u8cc7\u6df1\u5927\u4f6c : livepps <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             pFunc \u8981\u58f0\u660e\u6307\u9488\u51fd\u6570\u5427\uff0c\u58f0\u660e\u6709\u95ee\u9898                                                            <\/div>\n<\/p><\/div>\n<\/li>\n<li data-pid=\"1822936\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u8cc7\u6df1\u5927\u4f6c : levelworm <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             \u8fd9\u662f\u51fd\u6570\u5427\uff1f<br \/>\u8fd8\u6709\uff0c\u6211\u7edd\u903c\u5728\u4e4b\u524d\u770b\u5230\u5b8c\u5168\u4e00\u6837\u7684\u95ee\u9898\uff0cdeja vu\uff0c\u8fd9\u662f\u600e\u4e48\u4e86\uff01                                                            <\/div>\n<\/p><\/div>\n<\/li>\n<li data-pid=\"1822937\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u8cc7\u6df1\u5927\u4f6c : TaylorJack123 <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             @ligiggy \u6211\u9519\u4e86\uff0c\u606d\u559c\u4f60\u5199\u5bf9\u4e86^_^                                                            <\/div>\n<\/p><\/div>\n<\/li>\n<li>\n","protected":false},"excerpt":{"rendered":"<p>[C++] typedef \u6307\u9488\u51fd&hellip;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[],"tags":[],"_links":{"self":[{"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/posts\/109500"}],"collection":[{"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=109500"}],"version-history":[{"count":0,"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/posts\/109500\/revisions"}],"wp:attachment":[{"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=109500"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=109500"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=109500"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}