#include <iostream>
#include <list>
#include <algorithm>
#include <string>
using namespace std;
struct print
{
void operator()(const string& _str)
{
cout << _str << endl;
}
};
int main()
{
list<string> str_list;
str_list.push_front("hello");
str_list.push_front("world");
list<string> another_list;
another_list.push_back("hello");
another_list.push_back("world");
for_each(str_list.begin(), str_list.end(), print());
for_each(another_list.begin(), another_list.end(), print());
}
榪愯緇撴灉錛?/p>
world
hello
hello
world
綆鍗曠殑涓滆タ寰寰鑳借鏄庢繁鍒葷殑閬撶悊錛屽湪榪欎釜紼嬪簭閲岋紝鎴戜滑閬囧埌鐨勬湰璐ㄩ棶棰樻槸浠涔堬紵棣栧厛錛屾垜浠湁涓涓鍣紱鍏舵錛屾垜浠彲浠ュ線瀹瑰櫒閲岄潰鏀句笢瑗匡紝鏈鍚庯紝鎴戜滑鍙互閫氳繃綆楁硶鎶婁竴涓搷浣滄柦鍔犱簬榪欎釜瀹瑰櫒涓殑姣忎竴涓紙涔熷彲浠ユ槸閮ㄥ垎錛夊厓绱犱腑銆傝繖灝辨槸涓婇潰紼嬪簭涓嚌緇撶殑鏈川闂銆?/p>
MPL 鍙互鐪嬫垚鏄?STL 鐨勭紪璇戞湡鐗堟湰錛屾垨鑰呰鍏冪紪紼嬬増鏈傚畠鍚屾牱涔熸彁渚涗簡鍚勭瀹瑰櫒錛屽彧涓嶈繃瀹圭撼鐨勫璞′笉鏄暟鎹紝鑰屾槸綾誨瀷銆傚畠浠殑鏋勯犳柟寮忚娉曚笂姣旇緝綾諱技錛屾垨鑰呯敋鑷籌紝鎴戜互涓猴紝鏇存湁瓚d竴鐐癸細
#include <string>
#include <iostream>
#include <boost/mpl/at.hpp>
#include <boost/mpl/list.hpp>
#include <boost/mpl/push_front.hpp>
using namespace boost;
int main()
{
typedef mpl::list<> type_list1;
typedef mpl::push_front<type_list1, int>::type type_list2;
typedef mpl::push_front<type_list2, std::string>::type type_list;
// 鎴栬呰繖鏍鋒洿濂?br> typedef mpl::list<int, std::string> another_list;
std::cout << typeid(mpl::at_c<type_list, 0>::type).name() << std::endl;
std::cout << typeid(mpl::at_c<type_list, 1>::type).name() << std::endl;
std::cout << typeid(mpl::at_c<another_list, 0>::type).name() << std::endl;
std::cout << typeid(mpl::at_c<another_list, 1>::type).name() << std::endl;
}
紼嶅井瑙i噴涓涓嬨俶pl::list 灝辨槸 std::list 鐨勫厓緙栫▼鐗堟湰錛岃?mpl::push_front 鏄粈涔堝氨涓嶇敤鎴戣浜嗐俶pl::at_c 鏄竴涓厓緙栫▼綆楁硶錛屼綔鐢ㄧ浉褰撲簬榪愯鏈熺殑 [ ] 榪愮畻絎︼紝涔熷氨鏄緱鍒頒竴涓鍣ㄤ腑鍦ㄦ煇涓綅緗笂鐨勫厓绱犮傚湪 VC7.1 涓嬮潰錛屾墽琛岀粨鏋滄槸
class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >
int
int
class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >
榪欒窡榪愯鏈熺殑 list 鐨勮涓哄嚑涔庡畬鍏ㄤ竴鑷淬?/p>
褰撶劧錛宮pl 涔熸湁 for_each 錛岃屼笖鎴戜滑涔熷彲浠ヤ負 for_each 鎻愪緵涓涓厓緙栫▼ functor 銆備粈涔堟槸鍏冪紪紼?functor 錛熻繍琛屾椂鐨?functor 鏄竴涓彁渚涗簡 operator() 閲嶈澆鐨?struct 錛岃屽厓緙栫▼ functor 灝辨槸涓涓彁渚涗簡 operator() 妯℃澘鐨?struct 錛?/p>
#include <string>
#include <iostream>
#include <boost/mpl/at.hpp>
#include <boost/mpl/list.hpp>
#include <boost/mpl/push_front.hpp>
#include <boost/mpl/for_each.hpp>
using namespace boost;
struct print
{
template <class T>
void operator()(const T&)
{
std::cout << typeid(T).name() << std::endl;
}
};
int main()
{
typedef mpl::list<> type_list1;
typedef mpl::push_front<type_list1, int>::type type_list2;
typedef mpl::push_front<type_list2, std::string>::type type_list;
typedef mpl::list<int, std::string> another_list;
mpl::for_each<type_list>(print());
mpl::for_each<another_list>(print());
}
杈撳嚭涓庝笂闈嬌鐢?mpl::at_c 鐨勭▼搴忓畬鍏ㄧ浉鍚屻?/p>
褰撶劧錛屽埌鐜板湪涓烘錛岃繖浜涚▼搴忛兘榪樻槸鍙仠鐣欏湪綰補鐨勭帺鍏風▼搴忎笂錛岃兘涓嶈兘鍋氱偣紼嶅井鏈夌敤鐨勪簨鎯呭憿錛熷綋鐒跺彲浠ャ傚亣瀹氭垜浠湁榪欐牱涓涓戶鎵夸綋緋伙細鏍規槸涓涓娊璞$被 Product 錛屽畠鏈変竴浜涙淳鐢熺被錛屼緥濡?PC 錛?Printer 絳夌瓑錛屽畠浠殑鍏叡鏂規硶 SerialNo 浼氳繑鍥炶嚜宸辯殑浜у搧搴忓垪鍙鳳紝鑰岃繖涓簭鍒楀彿鏄湪鏋勯犵殑鏃跺欏喅瀹氱殑錛?/p>
class Product
{
public:
virtual std::string SerialNo()const = 0;
};
class PC : public Product
{
public:
PC(const std::string& _sn)
: sn_(_sn)
{}
std::string SerialNo()const
{
return sn_;
}
private:
std::string sn_;
};
class Printer : public Product
{
public:
Printer(const std::string& _sn)
: sn_(_sn)
{}
std::string SerialNo()const
{
return sn_;
}
private:
std::string sn_;
};
鐢?mpl::list 鎶婅繖浜涚被鍨嬫斁鍦ㄥ悓涓涓?list 閲岄潰褰撶劧涓嶅湪璇濅笅錛屼絾鏄垜浠笇鏈涙湁涓涓被浼?factory 妯″紡鐨勫疄鐜幫紝璁╂垜浠彲浠ヨ嚜鐢卞垱寤哄畠浠備笅闈㈢殑紼嬪簭鐢?mpl::for_each 涓?list 涓殑姣忎竴涓被鍨嬪垱寤轟竴涓疄渚嬶紝瀹冨綋鐒跺彲浠ヨ鎵╁睍鏉ュ仛浜涘緢鏈夌敤鐨勪簨鎯呫?/p>
#include <string>
#include <sstream>
#include <iostream>
#include <algorithm>
#include <list>
#include <boost/shared_ptr.hpp>
#include <boost/mpl/at.hpp>
#include <boost/mpl/list.hpp>
#include <boost/mpl/for_each.hpp>
using namespace boost;
class Product
{
public:
virtual std::string SerialNo()const = 0;
};
class PC : public Product
{
public:
PC(const std::string& _sn)
: sn_(_sn)
{}
std::string SerialNo()const
{
return sn_;
}
private:
std::string sn_;
};
class Printer : public Product
{
public:
Printer(const std::string& _sn)
: sn_(_sn)
{}
std::string SerialNo()const
{
return sn_;
}
private:
std::string sn_;
};
struct print
{
template <class T>
void operator()(const T& product)
{
std::cout << "Type: " << typeid(T).name()
<< " SerialNo: " << product.SerialNo() << std::endl;
}
};
// 鐢變簬 PC 鍜?Print 閮芥病鏈夐粯璁ょ殑 constructor 錛屽繀欏誨姞涓婅繖涓?br>template <class T>
struct wrap {};
struct Create
{
Create(const std::string& _line)
: line_(_line)
, serial_(0)
{}
template <class T>
void operator()(wrap<T>)
{
std::stringstream ss;
ss << line_ << '_' << serial_++;
shared_ptr<T> product(new T(ss.str()));
print()(*product);
}
std::string line_;
unsigned long serial_;
};
int main()
{
typedef mpl::list<Printer, PC> product_list;
mpl::for_each<product_list, wrap<mpl::_1> >(Create("line1"));
}
杈撳嚭錛?/p>
Type: class Printer SerialNo: line1_0
Type: class PC SerialNo: line1_1
鏈枃鏉ヨ嚜CSDN鍗氬錛岃漿杞借鏍囨槑鍑哄錛?a >http://blog.csdn.net/ralph623/archive/2005/10/15/504369.aspx
鏉ヨ嚜:http://www.shnenglu.com/shanoa/archive/2009/05/30/86143.html
鎺ヨЕ浜哹oost鐨勭姸鎬佹満錛屽彂鐜頒笉鏄兂璞′腑鐨勯偅涔堝ソ鐢紝鍦ㄤ竴浜涘湴鏂硅繕寰楃敤涓妋pl搴撻噷鐨勪笢瑗匡紝鐢變簬瀵規ā鏉垮厓緙栫▼涓嶆槸寰堢啛緇冿紝鎼炰簡濂戒簺澶╂墠綆楀紕鏄庣櫧榪欒姝葷殑mpl::list鐨勫師鐞嗗拰鐢ㄦ硶銆?br>boost鐨勭姸鎬佹満鏄睘浜庨潤鎬侀摼鎺ョ殑鐘舵佹満錛屼篃灝辨槸璇達紝瀹冪殑鍥劇粨鏋勬槸緙栬瘧鏈熼棿灝辯‘瀹氫簡鐨勶紝鍦ㄨ繍琛屾椂涓嶅彲浠ュ姩鎬侀厤緗傛墍浠ワ紝瀹冪殑鐢ㄩ旀槸鏈変竴瀹氬眬闄愭х殑錛屼絾鍦ㄤ竴鑸儏鍐典笅錛屽畠涓嶄粎寰堥氱敤錛岃屼笖鍦ㄤ綘浼氱敤騫剁啛緇冨湴鎯呭喌涓嬶紝榪樹細寰堝ソ鐢紝鐢ㄨ搗鏉ュ緢鑸掓湇錛岄昏緫涔熷緢鍚堢悊銆備笅闈㈠氨鏄竴孌典唬鐮侊紝褰撶劧涔熸槸鍊熼壌浜嗗埆浜虹殑涓滆タ錛岃嚜宸變慨鏀逛簡涓涓嬶紝鍦∕ainState涓坊鍔犱簡涓涓猅ransition鍋氫簡嫻嬭瘯錛屽洜涓烘鍓嶆垜榪樹笉鐭ラ亾涓涓姸鎬佸浣曞寘鍚涓猅ransition錛屽懙鍛碉紝鍘熸潵鏄敤mpl::list鏉ュ仛銆傝嚦浜庤繖涓姸鎬佹満鐨勫叆闂ㄦ暀紼嬶紝緗戜笂闅忓鍙鐨勪笁閮ㄦ洸錛氥奲oost 鐘舵佹満鍏ラ棬鏁欑▼銆嬭寰楀緢娓呮銆?br>
1.2 澧炲姞鍔ㄤ綔
姝ゆ椂鎴戜滑灝嗗彧鐢ㄤ竴縐嶅姩浣滐細transitions錛屾垜浠湪涓嬮潰鐨勪唬鐮佷腑鎻掑叆浜嗛粦浣撶殑閮ㄥ垎銆?/span>
鐜板湪鎴戜滑鏈変簡鎵鏈夌殑鐘舵侊紝騫跺湪閫傚綋鐨勪綅緗鍔犱簡鎵鏈夌殑榪佺Щ鍔ㄤ綔錛屽悓鏃舵垜浠篃鍚慡topWatch鍙戦佷簡涓浜涗簨浠躲傝繖涓姸鎬佹満浼氬敖鑱屽敖璐g殑鎸夋垜浠殑甯屾湜榪涜鐘舵佽縼縐伙紝浣嗕緷鐒剁幇鍦ㄨ繕娌℃湁鍏跺畠鐨勫姩浣溿?/span>
1.3 State-local瀛樺偍
涓嬩竴姝ユ垜浠皢璁╄繖涓猄top watch鐪熸鐨勮褰曟椂闂翠簡銆傛牴鎹畇top watch鎵澶勪笉鍚岀殑鐘舵侊紝鎴戜滑闇瑕佷笉鍚岀殑鍙橀噺銆?/span>
l Stopped鐘舵侊細闇瑕佷竴涓繚瀛橀濆幓鏃墮棿鐨勫彉閲忋?/span>
l Running鐘舵侊細闇瑕佷竴涓繚瀛橀濆幓鏃墮棿鐨勫彉閲忥紝榪橀渶瑕佷竴涓繚瀛樹笂涓嬈″惎鍔ㄧ殑鏃墮棿鐐圭殑鍙橀噺銆?/span>
鏃犺鐘舵佹満鍦ㄤ粈涔堢姸鎬佷笅錛屾垜浠兘蹇呴』瑙傚療閫濆幓鏃墮棿榪欎釜鍙橀噺銆傛澶栵紝褰撴垜浠悜鐘舵佹満鍙戦丒vReSet浜嬩歡鏃訛紝榪欎釜鍙橀噺搴旇琚疆涓?銆傚叾瀹冪殑鍙橀噺鍙槸鐘舵佹満鍦≧unning鐘舵佹椂闇瑕併傛棤璁轟綍鏃舵垜浠繘鍏unning鐘舵佹椂錛屽畠搴旇琚疆涓虹郴緇熸椂閽熺殑褰撳墠鏃墮棿銆傚綋鎴戜滑閫鍑篟unning鐘舵佹椂錛屾垜浠粎浠呬粠緋葷粺鏃墮挓鐨勫綋鍓嶆椂闂村噺鍘誨紑濮嬫椂闂達紙榪涘叆鏃惰褰曠殑鏃墮棿錛夛紝灝嗙粨鏋滃姞鍒伴濆幓鏃墮棿閲屽氨鍙互浜嗐?/span>
榪欎釜鐘舵佹満鐜板湪鍙互嫻嬮噺鏃墮棿浜嗭紝浣嗘槸鎴戜滑榪樹笉鑳界湅鍒扮粨鏋溿?/span>
鍦ㄨ繖閲岋紝State-local storage鐨勪紭鍔胯繕娌℃湁瀹屾垚鏄劇幇鍑烘潵銆傚湪FAQ欏圭洰“State-local storage閰峰湪鍝噷錛?#8221;涓紝浼氶氳繃涓庝竴涓病鏈夌敤State-local storage鐨凷top Watch鐨勬瘮杈冩潵璇存槑銆?/span>
1.4 鍦ㄧ姸鎬佹満澶栧緱鍒扮姸鎬佷俊鎭?/span>
涓轟簡鍙栧緱嫻嬮噺鐨勬椂闂達紝鎴戜滑闇瑕佷竴涓粠鐘舵佹満澶栧緱鍒扮姸鎬佷俊鎭殑鏈哄埗銆傛寜鎴戜滑鐜板湪鐨勭姸鎬佹満璁捐錛屽彲浠ユ湁涓ょ鏂規硶銆備負綆鍗曡搗瑙侊紝鎴戜滑鍦ㄨ繖閲岀敤涓涓綆鏁堢殑鏂瑰紡錛歴tate_cast<>()(鍦⊿topWatch2.cpp涓垜浠細鐢ㄤ竴涓◢澶嶆潅涓鐐圭殑鏇夸唬鏂規硶)錛?span style="COLOR: #000080">璇戣呮敞錛氬湪StopWatch2.cpp涓槸鍚戠姸鎬佹満鍙戦佷竴涓彇寰楅濆幓鏃墮棿鐨勪簨浠訛紝浠庝簨浠舵垚鍛橀噺涓皢閫濆幓鏃墮棿甯﹀洖鏉?/span> 錛夛紝浠庡瓧闈㈡剰鎬濆氨鍙互鐪嬪嚭錛屽畠鍦ㄨ涔変笂涓巇ynamic_cast鏈夌偣鐩鎬技銆備緥濡傦紝褰撴垜浠皟鐢╩yWatch.state_cast<const Stpped&>()鏃訛紝褰撶姸鎬佹満鍦⊿topped鐘舵佹椂錛屾垜浠細寰楀埌涓涓猄topped鐘舵佺被鐨勫紩鐢ㄣ傚惁鍒欙紝浼氭姏鍑簊td::bad_cast寮傚父銆傛垜浠彲浠ュ埄鐢ㄨ繖涓姛鑳芥潵瀹炵幇涓涓猄topWatch鐨勬垚鍛樺嚱鏁幫紝璁╁畠鐨勭粨鏋滆繑鍥為濆幓鐨勬椂闂淬傜劧鑰岋紝鎴戜滑涓嶆槸鍏堥棶涓涓嬬姸鎬佹満鍦ㄤ粈涔堢姸鎬侊紝鐒跺悗鍐嶅幓鐢ㄤ笉鍚岀殑鏂規硶璁$畻閫濆幓鏃墮棿錛岃屾槸灝嗚綆楁斁鍒癝topped鍜孯unning鐘舵佷腑錛岀敤涓涓帴鍙f潵鑾峰緱閫濆幓閫濆幓鏃墮棿銆?/span>
涓轟簡紜疄鐪嬪埌琚祴閲忕殑鏃墮棿錛屼綘搴旇鎯沖姙娉曞湪main()涓崟姝ユ墽琛屻係topWatch渚嬪瓙灝嗚繖涓▼搴忔墿灞曚負涓涓氦浜掑紡鐨勭粓绔▼搴忎簡銆?/span>
1 鍩虹涓婚錛氱琛?/strong>
涓嬮潰鎴戜滑瑕佷負涓涓満姊扮琛ㄥ緩妯′竴涓姸鎬佹満銆傝繖鏍蜂竴涓琛ㄩ氬父浼氭湁涓や釜鎸夐挳銆?br> * Start/Stop
* Reset
鍚屾椂鏈変袱縐嶇姸鎬侊細
* Stoped: 琛ㄩ拡鍋滅暀鍦ㄤ笂嬈″仠姝㈡椂鐨勪綅緗細
o 鎸変笅Reset鎸夐挳錛岃〃閽堝洖閫鍒?鐨勪綅緗傜琛ㄤ繚鎸佸湪Stoped鐘舵佷笉鍙樸?br> o 鎸変笅Start/Stop鎸夐挳錛岀琛ㄨ漿鍒癛unning鐘舵併?br> * Running: 琛ㄩ拡鍦ㄧЩ鍔紝騫舵寔緇樉紺鴻繃鍘葷殑鏃墮棿錛?/span>
o 鎸変笅Reset鎸夐挳錛岃〃閽堝洖閫鍒?鐨勪綅緗紝縐掕〃杞埌鍋滄鐘舵併?br> o 鎸変笅Start/Stop鎸夐挳錛岃漿鍒癝toped鐘舵併?br> 涓嬮潰鏄叾UML鍥撅細
1.1 瀹氫箟鐘舵佸拰浜嬩歡
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