茶余饭后来回顾我们熟悉的“Hello world program”

我们刚开始接触计算机语言大多从Hello world 开始，下面演示各种语言的Hello world program：

AKA 控制台

• ABC

WHILE (1=1) :

 WRITE "Hello World " 

• Ada

with Ada.Text_Io; use Ada.Text_Io;
procedure Hello is
begin
Put_Line ("Hello, world!");
end Hello;

• AmigaE

PROC main()
WriteF('Hello, World!')
ENDPROC

• APL

'Hello World'

• Assembly language

Accumulator-only architecture: DEC PDP-8, PAL-III assembler
See the Example section of the PDP-8 article.

• 
  Accumulator + index register machine: MOS 6502, CBM, ca65 asm

MSG: .ASCIIZ "Hello, world!"
LDX #0
LDA MSG,X ; load initial char
@LP: JSR $FFD2 ; CHROUT CBM KERNAL
INX
LDA MSG,X
BNE @LP
RTS
Accumulator/Index microcoded machine: Data General Nova, RDOS
See the example section of the Nova article.
Expanded accumulator machine: Intel x86, MS-DOS, TASM

MODEL SMALL
IDEAL
STACK 100H

DATASEG
MSG DB 'Hello, world!$'

CODESEG
MOV AX, @data
MOV DS, AX
MOV DX, OFFSET MSG
MOV AH, 09H ; DOS: output ASCII$ string
INT 21H
MOV AX, 4C00H
INT 21H
END

• General-purpose-register CISC: DEC PDP-11, RT-11, MACRO-11

.MCALL .REGDEF,.TTYOUT,.EXIT
.REGDEF

HELLO: MOV #MSG,R1
MOVB (R1),R0
LOOP: .TTYOUT
MOVB +(R1),R0
BNE LOOP
.EXIT

MSG: .ASCIZ /HELLO, WORLD!/
.END HELLO
CISC: VAX, VMS, MACRO32
.title hello
term_name: .ascid /SYS$INPUT/
term_chan: .blkw 1
out_iosb: .blkq 1
msg: .asciz /Hello, world!/

.entry start,0

; establish a channel for terminal I/O
$assign_s devnam=term_name,-
chan=term_chan
blbc r0,error

; queue the I/O request
$qio_s chan=term_chan,-
func=#io$_writevblk,-
iosb=out_iosb,-
p1=msg,-
p2=#13
blbc r0,error

$exit_s ; normal exit

error: halt ; error condition

.end start

• AWK

BEGIN { print "Hello, world!" }

• BASIC
• MS BASIC (traditional, unstructured)
  10 PRINT "Hello, world!"
  20 END
• TI-BASIC
  isp "Hello, world!"
• Structured BASIC
  print "Hello, world!"
• BCPL
  GET "LIBHDR"

LET START () BE
$(
WRITES ("Hello, world!*N")
$)

• 
  C

#include <stdio.h></stdio.h>

int main(void) {
printf("Hello, world!\n");
return 0;
}

• C++

#include <iostream><br> using namespace std;</iostream>

int main() {
cout << "Hello, world!" << endl;
return 0;
}

• C#

class HelloWorldApp {
public static void Main() {
System.Console.WriteLine("Hello, world!");
}
}

• Clean

module hello

Start :: String
Start = "Hello, world"

• CLIST

PROC 0
WRITE Hello, World!

• COBOL

IDENTIFICATION DIVISION.
PROGRAM-ID. HELLO-WORLD.

ENVIRONMENT DIVISION.

DATA DIVISION.

PROCEDURE DIVISION.
DISPLAY "Hello, world!".
STOP RUN.

• Common Lisp

(format t "Hello world!~%")

• Eiffel

class HELLO_WORLD

creation
make
feature
make is
local
io:BASIC_IO
do
!!io
io.put_string("%N Hello, world!")
end -- make
end -- class HELLO_WORLD

• Erlang

-module(hello).
-export([hello_world/0]).

hello_world() -> io:fwrite("Hello, world!\n").

• Forth

." Hello, world!" CR

• Fortran （偶大学学的课程）

PROGRAM HELLO
WRITE(*,10)
10 FORMAT('Hello, world!')
STOP
END

• Haskell

module HelloWorld (main) where

main = putStr "Hello World\n"

• 
  Iptscrae

ON ENTER {
"Hello, " "World!" & SAY
}

• Java

public class Hello {
public static void main(String[] args) {
System.out.println("Hello, world!");
}
}

• Logo

print [hello world!]

• Lua

print "Hello, world!"

• MIXAL

TERM EQU 19 the MIX console device number
ORIG 1000 start address
START OUT MSG(TERM) output data at address MSG
HLT halt execution
MSG ALF "MIXAL"
ALF " HELL"
ALF "O WOR"
ALF "LD "
END START end of the program

• MSDOS batch

@echo off
echo Hello, world!

• OCaml
  let _ =
  print_endline "Hello world!";;
• OPL
  PROC hello:
  PRINT "Hello, World"
  ENDP
• Pascal
  program Hello;
  begin
  writeln('Hello, world!');
  end.
• Perl

print "Hello, world!\n";

• PHP

<?php <br /> print("Hello, world!");
?>

• Pike
  #!/usr/local/bin/pike
  int main() {
  write("Hello, world!\n");
  return 0;
  }
• PL/I

Test: procedure options(main);
declare My_String char(20) varying initialize('Hello, world!');
put skip list(My_String);
end Test;

• Python

print "Hello, world!"

• REXX, also NetRexx and Object REXX

say "Hello, world!"

• Ruby

print "Hello, world!\n"

• Sather

class HELLO_WORLD is
main is
#OUT+"Hello World\n";
end;
end;

• Scheme

(display "Hello, world!")
(newline)

• sed (requires at least one line of input)

sed -ne '1s/.*/Hello, world!/p'

• Self

'Hello, World!' uppercase print.

• 
  Smalltalk

Transcript show: 'Hello, world!'

• SML

print "Hello, world!\n";

• SNOBOL

OUTPUT = "Hello, world!"
END

• SQL

create table MESSAGE (TEXT char(15));
insert into MESSAGE (TEXT) values ('Hello, world!');
select TEXT from MESSAGE;
drop table MESSAGE;
Or, more simply

print 'Hello, World.'

• StarOffice Basic

sub main
print "Hello, World"
end sub

• Tcl

puts "Hello, world!"

• Turing

put "Hello, world!"

• UNIX-style shell

echo 'Hello, world!'

• Romanian pseudocode (UBB Cluj-Napoca)

Algoritmul Salut este:
fie s:="Hello, world";
tipareste s;
sf-Salut

• 传统图形界面应用开发工具
• 
  C++ bindings for GTK graphics toolkit

#include <iostream><br> #include <gtkmm main=""><br> #include <gtkmm button=""><br> #include <gtkmm window=""><br> using namespace std;</gtkmm></gtkmm></gtkmm></iostream>

class HelloWorld : public Gtk::Window {
public:
HelloWorld();
virtual ~HelloWorld();
protected:
Gtk::Button m_button;
virtual void on_button_clicked();

};

HelloWorld::HelloWorld()
: m_button("Hello, world!") {
set_border_width(10);
m_button.signal_clicked().connect(SigC:lot(*this,
&HelloWorld::on_button_clicked));
add(m_button);
m_button.show();
}

HelloWorld::~HelloWorld() {}

void HelloWorld::on_button_clicked() {
cout << "Hello, world!" << endl;
}

int main (int argc, char *argv[]) {
Gtk::Main kit(argc, argv);
HelloWorld helloworld;
Gtk::Main::run(helloworld);
return 0;
}

• Java

import java.awt.*;
import java.awt.event.*;

public class HelloFrame extends Frame {
HelloFrame(String title) {
super(title);
}
public void paint(Graphics g) {
super.paint;
java.awt.Insets ins = this.getInsets();
g.drawString("Hello, world!", ins.left + 25, ins.top + 25);
}
public static void main(String args [])
{
HelloFrame fr = new HelloFrame("Hello");

fr.addWindowListener(
new WindowAdapter() {
public void windowClosing(WindowEvent e)
{
System.exit( 0 );
}
}
);
fr.setResizable(true);
fr.setSize(500, 100);
fr.setVisible(true);
}
}

• 
  Qt toolkit (in C++)

#include <qapplication.h><br> #include <qpushbutton.h><br> #include <qwidget.h><br> #include <iostream></iostream></qwidget.h></qpushbutton.h></qapplication.h>

class HelloWorld : public QWidget
{
Q_OBJECT

public:
HelloWorld();
virtual ~HelloWorld();
public slots:
void handleButtonClicked();
QPushButton *mPushButton;
};

HelloWorld::HelloWorld() :
QWidget(),
mPushButton(new QPushButton("Hello, World!", this))
{
connect(mPushButton, SIGNAL(clicked()), this, SLOT(handleButtonClicked()));
}

HelloWorld::~HelloWorld() {}

void HelloWorld::handleButtonClicked()
{
std::cout << "Hello, World!" << std::endl;
}

int main(int argc, char *argv[])
{
QApplication app(argc, argv);
HelloWorld helloWorld;
app.setMainWidget(&helloWorld);
helloWorld.show();
return app.exec();
}

• Visual Basic

MsgBox "Hello, world!"

• Windows API (in C)

#include <windows.h></windows.h>

LRESULT CALLBACK WindowProcedure(HWND, UINT, WPARAM, LPARAM);

char szClassName[] = "MainWnd";
HINSTANCE hInstance;

int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow)
{
HWND hwnd;
MSG msg;
WNDCLASSEX wincl;

hInstance = hInst;

wincl.cbSize = sizeof(WNDCLASSEX);
wincl.cbClsExtra = 0;
wincl.cbWndExtra = 0;
wincl.style = 0;
wincl.hInstance = hInstance;
wincl.lpszClassName = szClassName;
wincl.lpszMenuName = NULL; //No menu
wincl.lpfnWndProc = WindowProcedure;
wincl.hbrBackground = (HBRUSH)(COLOR_WINDOW + 1); //Color of the window
wincl.hIcon = LoadIcon(NULL, IDI_APPLICATION); //EXE icon
wincl.hIconSm = LoadIcon(NULL, IDI_APPLICATION); //Small program icon
wincl.hCursor = LoadCursor(NULL, IDC_ARROW); //Cursor

if (!RegisterClassEx(&wincl))
return 0;

hwnd = CreateWindowEx(0, //No extended window styles
szClassName, //Class name
"", //Window caption
WS_OVERLAPPEDWINDOW & ~WS_MAXIMIZEBOX,
CW_USEDEFAULT, CW_USEDEFAULT, //Let Windows decide the left and top positions of the window
120, 50, //Width and height of the window,
NULL, NULL, hInstance, NULL);

//Make the window visible on the screen
ShowWindow(hwnd, nCmdShow);

//Run the message loop
while (GetMessage(&msg, NULL, 0, 0))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}
return msg.wParam;
}

LRESULT CALLBACK WindowProcedure(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
PAINTSTRUCT ps;
HDC hdc;
switch (message)
{
case WM_PAINT:
hdc = BeginPaint(hwnd, &ps);
TextOut(hdc, 15, 3, "Hello, world!", 13);
EndPaint(hwnd, &ps);
break;
case WM_DESTROY:
PostQuitMessage(0);
break;
default:
return DefWindowProc(hwnd, message, wParam, lParam);
}
return 0;
}

基于web图形用户界面

• 
  Java applet

Java applets work in conjunction with HTML files.

HelloWorld Program says:

<applet height="100" width="600" code="HelloWorld"> <br>??? </applet>

import java.applet.*;
import java.awt.*;

public class HelloWorld extends Applet {
public void paint(Graphics g) {
g.drawString("Hello, world!", 100, 50);
}
}

• JavaScript, aka ECMAScript

JavaScript is a scripting language used in HTML files. To demo this program Cut and Paste the following code into any HTML file.

???? function helloWorld()
???? {
???????? javascript: alert("Hello, world!");
???? }
????

onclick="javascript:helloWorld();">Hello World Example

An easier method uses JavaScript implicitly, calling the reserved alert function. Cut and paste the following line inside the .... HTML tags.

Hello World Example

An even easier method involves using popular browsers' support for the virtual 'javascript' protocol to execute JavaScript code. Enter the following as an Internet address (usually by pasting into the address box):

javascript:alert('Hello, world!')

• XUL

<window there="" gatekeeper="" keymaster="" www="" http="" xmlns="&lt;A href=">http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"&gt;<br><box align="center"><br><label value="Hello, world!"><br></label></box><br></window>

• 文档格式
• ASCII
  The following sequence of characters, expressed in hexadecimal notation (with carriage return and newline characters at end of sequence):

48 65 6C 6C 6F 2C 20 77 6F 72 6C 64 21 0D 0A

• HTML

Hello, world!

• PostScript

/font /Courier findfont 24 scalefont
font setfont
100 100 moveto
(Hello world!) show
showpage

• TeX

\font\HW=cmr10 scaled 3000
\leftline{\HW Hello world}
\bye