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Hello World Examples
php
PHP can be embedded into an html file, and interpreted at runtime for dynamic web page content. It can also be executed at the command line by using the php program.
| plan | with functions and variables |
|---|---|
<?php echo "Hello World!"; ?> | <?php
$myString = "Hello World!";
function printMyString(){
global $myString;
echo $myString;
}
printMyString();
?>
|
html
HTML by itself does not have functions or variables. It is a tagged language most commonly used to display a web page.
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"> <html> <head> <title>Hello World Example</title> </head> <body> <h1>Hello World Example</h1> <p>Hello World!</p> </body> </html>
c
C is a procedural, structured language that does not have objects. C is extended by other languages, such as C++ and Objective-C.
| plain | with functions and variables |
|---|---|
#include <stdio.h>
int main(){
printf("Hello World!\n");
return 0;
}
| #include <stdio.h>
const char * myString;
void printMyString(){
printf("%s\n",myString);
return;
}
int main(){
myString = "Hello World!";
printMyString();
return 0;
}
|
objective-c
Objective-C is an extension of c, so a plain version will not be shown here.
| with functions and variables |
|---|
#import <Foundation/NSObject.h>
#import <Foundation/NSString.h>
@interface Hello:NSObject{
NSString *myString;
}
-(void)printMyString;
@end
@implementation Hello
-(void)printMyString{
myString = [NSString stringWithString:@"Hello World!"];
NSLog(myString);
}
@end
int main( int argc, const char *argv[] ) {
NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];
Hello *h = [[Hello alloc] init];
[h printMyString];
[pool release];
return 0;
}
|
cpp
java
| plain | with functions and variables |
|---|---|
public class HelloWorld{
public static void main(String args[]){
System.out.println("Hello World!");
}
}
| public class HelloWorldVar{
private String myString = "Hello World!";
private void printMyString(){
System.out.println(myString);
}
public static void main(String args[]){
HelloWorldVar hw = new HelloWorldVar();
hw.printMyString();
}
}
|
javascript
perl
| plain | with functions and variables |
|---|---|
#!/usr/bin/perl print "Hello World!\n"; | #!/usr/bin/perl -w # the 'w' tells perl to inform you of any
# warnings encountered
use strict; # tell perl to impose strict verification,
# and output additional warnings
$myString = "Hello World!"; # $myString is a global variable
sub printMyString { # sub is used to define a subroutine, or
# function in perl;
print $myString; # this instance of $myString references
# the global $myString variable;
}
sub printLocalString {
my $myString = "Hello Moon!"; # the my operator marks this instance of
# $myString as private;
print $myString; # this statement is using the private
# $myString above;
}
printMyString(); # call a subroutine
printLocalString(); # call a subroutine
|