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Objective-C - Programming language

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Objective-C is a programming language created in 1984 by Brad Cox.

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Objective-C is a general-purpose, object-oriented programming language that adds Smalltalk-style messaging to the C programming language. It was the main programming language used by Apple for the OS X and iOS operating systems, and their respective application programming interfaces (APIs) Cocoa and Cocoa Touch prior to the introduction of Swift. The programming language Objective-C was originally developed in the early 1980s. Read more on Wikipedia...

Example from Riju:
#import <Foundation/Foundation.h> int main() { NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init]; NSLog(@"Hello, world!"); [pool drain]; return 0; }
Example from hello-world:
/* Build on OS X: clang -framework Foundation -fobjc-arc objc.m -o objc Build on Linux with GNUstep: clang `gnustep-config --objc-flags` `gnustep-config --base-libs` -fobjc-nonfragile-abi -fobjc-arc objc.m -o objc */ #import <Foundation/Foundation.h> int main(void) { NSLog(@"Hello World"); }
/* Hello World in Objective-C. ** Since the standard implementation is identical to K&R C, ** a version that says hello to a set of people passed on ** the command line is shown here. */ #include <stdio.h> #include <objpak.h> int main(int argc,char **argv) { id set = [Set new]; argv++;while (--argc) [set add:[String str:*argv++]]; [set do:{ :each | printf("hello, %s!\n",[each str]); }]; return 0; }
Example from Linguist:
#import "Foo.h" @implementation Foo @end
Example from Wikipedia:
-(void) firstLabel: (int)param1 secondLabel: (int)param2;
Objective-C Keywords
auto break case char const continue default do double else enum extern float for goto if inline int long register restrict return short signed sizeof static struct switch typedef union unsigned void volatile while _Bool _Complex _Imaginary BOOL Class bycopy byref id IMP in inout nil NO NULL oneway out Protocol SEL self Super YES @ @interface @end @implementation @protocol @class @public @protected @private @property @try @throw @catch() @finally @synthesize @dynamic @selector atomic nonatomic retain

Language features

Feature Supported Token Example
Conditionals โœ“
Switch Statements โœ“
Constants โœ“
While Loops โœ“
MultiLine Comments โœ“ /* */
/* A comment
Print() Debugging โœ“ printf
Comments โœ“
// A comment
Message Passing โœ“
Line Comments โœ“ //
// A comment
Interfaces โœ“
@protocol Printing
   -(void) print;
File Imports โœ“
// #import ensures that a file is only ever included once so that you never have a problem with recursive includes.
Constructors โœ“
Pointers โœ“
Single Dispatch โœ“
Strings โœ“ "
"hello world"
Scientific Notation โœ“
Case Sensitivity โœ“
Assignment โœ“
Increment and decrement operators โœ“
Zero-based numbering โœ“
Variadic Functions โœ“
double average(int count, ...)
Operators โœ“
1 + 1;
Manual Memory Management โœ“
int main(void)
  int *poin = malloc(4);
Macros โœ“
#define min(X, Y)  ((X) < (Y) ? (X) : (Y))
  x = min(a, b);          โ†’  x = ((a) < (b) ? (a) : (b));
  y = min(1, 2);          โ†’  y = ((1) < (2) ? (1) : (2));
  z = min(a + 28, *p);    โ†’  z = ((a + 28) < (*p) ? (a + 28) : (*p));
Integers โœ“
int pldb = 80766866;
Type Casting โœ“
double da = 3.3;
double db = 3.3;
double dc = 3.4;
int result = (int)da + (int)db + (int)dc; //result == 9
Directives โœ“
#define height 10
Gotos โœ“
// C/C++ program to check if a number is 
// even or not using goto statement 
using namespace std; 
// function to check even or not 
void checkEvenOrNot(int num) 
    if (num % 2 == 0) 
        goto even; // jump to even 
        goto odd; // jump to odd 
    cout << num << " is evenn"; 
    return; // return if even 
    cout << num << " is oddn"; 
// Driver program to test above function 
int main() 
    int num = 26; 
    return 0; 
Structs โœ“
struct account {
  int account_number;
  char *first_name;
  char *last_name;
  float balance;
Symbol Tables โœ“
// Declare an external function
extern double bar(double x);

// Define a public function
double foo(int count)
    double  sum = 0.0;

    // Sum all the values bar(1) to bar(count)
    for (int i = 1;  i <= count;  i++)
        sum += bar((double) i);
    return sum;
// Symbol Table:
// Symbol name|Type|Scope
// bar|function, double|extern
// x|double|function parameter
// foo|function, double|global
// count|int|function parameter
// sum|double|block local
// i|int|for-loop statement
Bitwise Operators โœ“
int i = 4; /* bit pattern equivalent is binary 100 */
int j = i << 2; /* makes it binary 10000, which multiplies the original number by 4 i.e. 16 */
Assert Statements โœ“
int i, a[10];
for (i = 0; i < 10; ++i)
  assert(0 <= i && i < 10);
  a[i] = 10-i;
for (i = 0; i < 10; ++i)
  assert(0 <= i && i < 10);
  assert(0 <= a[i] && a[i] < 10);
  a[a[i]] = a[i];
Ternary operators โœ“
int main(void) { printf("%d", 1 ? 1 : 0); }
Characters โœ“
char character = 'P';
Booleans โœ“
Enums โœ“
enum Gender {
Case Insensitive Identifiers X
Semantic Indentation X
Operator Overloading X
Garbage Collection X
Fixed Point Numbers X
Exceptions X
Classes X
Access Modifiers X
Templates X
Multiple Inheritance X
Namespaces X
Regular Expression Syntax Sugar X
Variable Substitution Syntax X

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