The Evolution of a Programmer

High School/Jr.High

	10 PRINT "HELLO WORLD"
	20 END

First year in College

	program Hello(input, output)
	  begin
	    writeln('Hello World')
	  end.

Senior year in College

	(defun hello
	  (print
	    (cons 'Hello (list 'World))))

New professional

	#include <stdio.h>
	void main(void)
	{
	  char *message[] = {"Hello ", "World"}; 
	  int i;
	    
	  for(i = 0; i < 2; ++i)
	    printf("%s", message[i]);
	    printf("\n");
	}

Seasoned professional

	#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 << endl;

	  return(0);
	}

Master Programmer

	[
	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);
	}

Apprentice Hacker

	#!/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;

Experienced Hacker

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

Seasoned Hacker

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

Guru Hacker

	% cat
	Hello, world.
	^D

New Manager

	10 PRINT "HELLO WORLD"
	20 END

Middle Manager

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

Senior Manager

	% zmail jim
	I need a "Hello, world." program by this afternoon.

Chief Executive

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