程序员的进化——从学生到首席执行官

--------------------------------------------------------------------------------
中学阶段

          10 PRINT "HELLO WORLD"
          20 END
--------------------------------------------------------------------------------
大学一年级

          program Hello(input, output)
            begin
              writeln('Hello World')
            end.
--------------------------------------------------------------------------------
大学高年级

          (defun hello
            (print
              (cons 'Hello (list 'World))))
--------------------------------------------------------------------------------
初级程序员

          #include <stdio.h>
          void main(void)
          {
            char *message[] = {"Hello ", "World"};
            int i;

            for(i = 0; i < 2; ++i)
              printf("%s", message[i]);
            printf("/n");
          }
--------------------------------------------------------------------------------
编程老鸟

          #include <iostream.h>
          #include <string.h>

          class string
          {
          private:
            int size;
            char *ptr;

          public:
            string() : size(0), ptr(new char('/0')) {}

            string(const string &s) : size(s.size)
            {
              ptr = new char[size + 1];
              strcpy(ptr, s.ptr);
            }

            ~string()
            {
              delete [] ptr;
            }

            friend ostream &operator <<(ostream &, const string &);
            string &operator=(const char *);
          };

          ostream &operator<<(ostream &stream, const string &s)
          {
            return(stream << s.ptr);
          }

          string &string::operator=(const char *chrs)
          {
            if (this != &chrs)
            {
              delete [] ptr;
             size = strlen(chrs);
              ptr = new char[size + 1];
              strcpy(ptr, chrs);
            }
            return(*this);
          }

          int main()
          {
            string str;

            str = "Hello World";
            cout << str << end

            return(0);
          }
--------------------------------------------------------------------------------
编程高手

          [
          uuid(2573F8F4-CFEE-101A-9A9F-00AA00342820)
          ]
          library LHello
          {
              // bring in the master library
              importlib("actimp.tlb");
              importlib("actexp.tlb");

              // bring in my interfaces
              #include "pshlo.idl"

              [
              uuid(2573F8F5-CFEE-101A-9A9F-00AA00342820)
              ]
              cotype THello
           {
           interface IHello;
           interface IPersistFile;
           };
          };

          [
          exe,
          uuid(2573F890-CFEE-101A-9A9F-00AA00342820)
          ]
          module CHelloLib
          {

              // some code related header files
              importheader(<windows.h>);
              importheader(<ole2.h>);
              importheader(<except.hxx>);
              importheader("pshlo.h");
              importheader("shlo.hxx");
              importheader("mycls.hxx");

              // needed typelibs
              importlib("actimp.tlb");
              importlib("actexp.tlb");
              importlib("thlo.tlb");

              [
              uuid(2573F891-CFEE-101A-9A9F-00AA00342820),
              aggregatable
              ]
              coclass CHello
           {
           cotype THello;
           };
          };

          #include "ipfix.hxx"

          extern HANDLE hEvent;

          class CHello : public CHelloBase
          {
          public:
              IPFIX(CLSID_CHello);

              CHello(IUnknown *pUnk);
              ~CHello();

              HRESULT  __stdcall PrintSz(LPWSTR pwszString);

          private:
              static int cObjRef;
          };

          #include <windows.h>
          #include <ole2.h>
          #include <stdio.h>
          #include <stdlib.h>
          #include "thlo.h"
          #include "pshlo.h"
          #include "shlo.hxx"
          #include "mycls.hxx"

          int CHello::cObjRef = 0;

          CHello::CHello(IUnknown *pUnk) : CHelloBase(pUnk)
          {
              cObjRef++;
              return;
          }

          HRESULT  __stdcall  CHello::PrintSz(LPWSTR pwszString)
          {
              printf("%ws/n", pwszString);
              return(ResultFromScode(S_OK));
          }

          CHello::~CHello(void)
          {

          // when the object count goes to zero, stop the server
          cObjRef--;
          if( cObjRef == 0 )
              PulseEvent(hEvent);

          return;
          }

          #include <windows.h>
          #include <ole2.h>
          #include "pshlo.h"
          #include "shlo.hxx"
          #include "mycls.hxx"

          HANDLE hEvent;

           int _cdecl main(
          int argc,
          char * argv[]
          ) {
          ULONG ulRef;
          DWORD dwRegistration;
          CHelloCF *pCF = new CHelloCF();

          hEvent = CreateEvent(NULL, FALSE, FALSE, NULL);

          // Initialize the OLE libraries
          CoInitializeEx(NULL, COINIT_MULTITHREADED);

          CoRegisterClassObject(CLSID_CHello, pCF, CLSCTX_LOCAL_SERVER,
              REGCLS_MULTIPLEUSE, &dwRegistration);

          // wait on an event to stop
          WaitForSingleObject(hEvent, INFINITE);

          // revoke and release the class object
          CoRevokeClassObject(dwRegistration);
          ulRef = pCF->Release();

          // Tell OLE we are going away.
          CoUninitialize();

          return(0);
          }

          extern CLSID CLSID_CHello;
          extern UUID LIBID_CHelloLib;

          CLSID CLSID_CHello = { /* 2573F891-CFEE-101A-9A9F-00AA00342820 */
              0x2573F891,
              0xCFEE,
              0x101A,
              { 0x9A, 0x9F, 0x00, 0xAA, 0x00, 0x34, 0x28, 0x20 }
          };

          UUID LIBID_CHelloLib = { /* 2573F890-CFEE-101A-9A9F-00AA00342820 */
              0x2573F890,
              0xCFEE,
              0x101A,
              { 0x9A, 0x9F, 0x00, 0xAA, 0x00, 0x34, 0x28, 0x20 }
          };

          #include <windows.h>
          #include <ole2.h>
          #include <stdlib.h>
          #include <string.h>
          #include <stdio.h>
          #include "pshlo.h"
          #include "shlo.hxx"
          #include "clsid.h"

          int _cdecl main(
          int argc,
          char * argv[]
          ) {
          HRESULT  hRslt;
          IHello        *pHello;
          ULONG  ulCnt;
          IMoniker * pmk;
          WCHAR  wcsT[_MAX_PATH];
          WCHAR  wcsPath[2 * _MAX_PATH];

          // get object path
          wcsPath[0] = '/0';
          wcsT[0] = '/0';
          if( argc > 1) {
              mbstowcs(wcsPath, argv[1], strlen(argv[1]) + 1);
              wcsupr(wcsPath);
              }
          else {
              fprintf(stderr, "Object path must be specified/n");
              return(1);
              }

          // get print string
          if(argc > 2)
              mbstowcs(wcsT, argv[2], strlen(argv[2]) + 1);
          else
              wcscpy(wcsT, L"Hello World");

          printf("Linking to object %ws/n", wcsPath);
          printf("Text String %ws/n", wcsT);

          // Initialize the OLE libraries
          hRslt = CoInitializeEx(NULL, COINIT_MULTITHREADED);

          if(SUCCEEDED(hRslt)) {

              hRslt = CreateFileMoniker(wcsPath, &pmk);
              if(SUCCEEDED(hRslt))
           hRslt = BindMoniker(pmk, 0, IID_IHello, (void **)&pHello);

              if(SUCCEEDED(hRslt)) {

           // print a string out
           pHello->PrintSz(wcsT);

           Sleep(2000);
           ulCnt = pHello->Release();
           }
              else
           printf("Failure to connect, status: %lx", hRslt);

              // Tell OLE we are going away.
              CoUninitialize();
              }

          return(0);
          }
--------------------------------------------------------------------------------
黑客初阶

          #!/usr/local/bin/perl
          $msg="Hello, world./n";
          if ($#ARGV >= 0) {
            while(defined($arg=shift(@ARGV))) {
              $outfilename = $arg;
              open(FILE, ">" . $outfilename) || die "Can't write $arg: $!/n";
              print (FILE $msg);
              close(FILE) || die "Can't close $arg: $!/n";
            }
          } else {
            print ($msg);
          }
          1;
--------------------------------------------------------------------------------
黑客有成

          #include <stdio.h>
          #define S "Hello, World/n"
          main(){exit(printf(S) == strlen(S) ? 0 : 1);}
--------------------------------------------------------------------------------
黑客高手

          % cc -o a.out ~/src/misc/hw/hw.c
          % a.out
--------------------------------------------------------------------------------
黑客大虾

          % cat
          Hello, world.
          ^D
--------------------------------------------------------------------------------
初级经理

          10 PRINT "HELLO WORLD"
          20 END
--------------------------------------------------------------------------------
中级经理

          mail -s "Hello, world." bob@b12
          Bob, could you please write me a program that prints "Hello, world."?
          I need it by tomorrow.
          ^D
--------------------------------------------------------------------------------
高级经理

          % zmail jim
          I need a "Hello, world." program by this afternoon.
--------------------------------------------------------------------------------
首席执行官

          % letter
          letter: Command not found.
          % mail
          To: ^X ^F ^C
          % help mail
          help: Command not found.
          % damn!
          !: Event unrecognized
          % logout
--------------------------------------------------------------------------------