类模板编程示例一

allege.h头文件

#ifndef _ALLEGE_H#define _ALLEGE_H#include<stdio.h>#include<assert.h>#include<stdlib.h>inline void allege_error(int arg,const char* msg){if (!arg){fprintf(stderr,"error: %s\n",msg);#ifdef NDEBUGexit(1);#endif}}#define allege(expr,msg) { allege_error((expr)?1:0,msg);  assert(expr);}#define allegemem(expr)  allege(expr,"out of memory")#define allegefile(expr) allege(expr,"can't open file")#endif

tstash.h头文件

#ifndef TSTASH_H#define TSTASH_H#include <stdlib.h>#include <assert.h>#include "allege.h"enum owns{no=0,yes=1,Default};template<class T,int sz>class tstashiter;template<class T,int size=20>class tstash{int quantity;int next;owns own;void inflate(int increase=size);protected:T** storage;public:tstash(owns own=yes);~tstash();int Owns() const{return own;}void Owns(owns newown){own=newown;}int add(T* element);int remove(int index,owns d=Default);T* operator[](int index);int cout() const{return next;}friend class tstashiter<T,size>;};template<class T,int size=20>class tstashiter{tstash<T,size> & ts;int index;public:tstashiter(tstash<T,size>& TS):ts(TS),index(0){}tstashiter(const tstashiter<T,size>& RS):ts(tstashiter.ts),index(tstashiter.index){}void forward(int amount){index+=amount;if (index>=ts.next){index=ts.next-1;}}void backward(int amount){index-=amount;if (index<0){index=0;}}int operator++(){if (++index>=ts.next)return 0;return 1;}int operator++(int) {return operator++();}int operator--(){if(--index<0)return 0;return 1;}int operator--(int) {return operator--();}operator int(){return (index>=0 && index<ts.next);}T* operator->(){T* t=ts.storage[index];if(t)return t;allege(0,"tstashiter operator-> return 0");return 0;}int remove(owns d=Default){return ts.remove(index,d);}};template<class T,int sz>tstash<T,sz>::tstash(owns wns):own(wns){quantity=0;storage=0;next=0;}template<class T,int sz>tstash<T,sz>::~tstash(){if(!storage)return ;if (own==yes){for (int i=0;i<cout();i++){delete storage[i];}}free(storage);}template<class T,int sz> int tstash<T,sz>::add(T* element){if (next>=quantity){inflate();}storage[next++]=element;return (next-1);}template<class T,int sz>int tstash<T,sz>::remove(int index,owns d){if (index>=next || index<0)return 0;switch (d){case Default:if (own!=yes)break;case yes:delete storage[index];case no:storage[index]=0;}return 1;}template<class T,int sz>inline T* tstash<T,sz>::operator[](int index){assert(index<next && index>=0);return storage[index];}template<class T,int sz>void tstash<T,sz>::inflate(int increase){void *V=realloc(storage,(quantity+increase)*sizeof(T*));//assert(V!=NULL);allegemem(V);storage=(T**)V;quantity+=increase;}#endif

源文件：

#include "tstash.h"#include <iostream>#include <fstream>#include "allege.h"#include <string>using namespace std;const bufsize=256;ofstream out("tstest.out");ofstream strout("strtest.out");class Int{int i;public:Int(int I=0):i(I){out<<">"<<i<<endl;}~Int(){out<<"~"<<i<<endl;}operator int() const {return i;} friend ostream& operator<<(ostream& os,const Int& x){return os<<x.i;}};class stringV:public string{char* s;stringV(const stringV&);void operator=(stringV&);public:stringV(const char *sv=""){//s=(char*)malloc(strlen(sv)+1);s=new char[strlen(sv)+1];allegemem(s);strcpy(s,sv);}~stringV(){delete s;}operator const char*() const {return s;}char * str() const {return s;}friend stringV* makestring(const char *s){return new stringV(s);}static stringV* make(const char *s){return new stringV(s);}friend ostream& operator<<(ostream& os,const stringV& sv){return os<<sv.s;}};void main(){tstash<Int> intstash;for (int i=0;i<30;i++){intstash.add(new Int(i));}tstashiter<Int> init(intstash);init.forward(5);for (int j=0;j<20;j++,init++){init.remove();}for (int k=0;k<intstash.cout();k++){if(intstash[k])out<<*intstash[k]<<endl;}ifstream file("readInfor.txt");allegefile(file);char buf[bufsize];tstash<stringV> stringVstash;while (file.getline(buf,bufsize)){stringVstash.add(makestring(buf));}for (int u=0;u<stringVstash.cout();u++){if (stringVstash[u]){strout<<*stringVstash[u]<<endl;}}tstashiter<stringV> it(stringVstash);int jp=25;it.forward(jp);while(it){strout<<jp++<<it->str()<<endl;it++;}}