#import <Foundation/Foundation.h>

@interface Point : NSObject
@property (nonatomic, assign) int x;
@property (nonatomic, assign) int y;
@end

@implementation Point
@end

int main(int argc, const char * argv[]) {
    @autoreleasepool {
        // Objective-C offers several formatting options for various data types.
        // Here are some examples of common string formatting tasks.

        Point *p = [[Point alloc] init];
        p.x = 1;
        p.y = 2;

        // For basic object description, use %@
        NSLog(@"struct1: %@", p);

        // To print the type of a value, use %@
        NSLog(@"type: %@", NSStringFromClass([p class]));

        // Formatting booleans
        NSLog(@"bool: %d", YES);

        // There are many options for formatting integers.
        // Use %d for standard, base-10 formatting.
        NSLog(@"int: %d", 123);

        // This prints a binary representation.
        NSLog(@"bin: %b", 14);

        // This prints the character corresponding to the given integer.
        NSLog(@"char: %c", 33);

        // %x provides hex encoding.
        NSLog(@"hex: %x", 456);

        // There are also several formatting options for floats.
        // For basic decimal formatting use %f.
        NSLog(@"float1: %f", 78.9);

        // %e and %E format the float in (slightly different versions of) scientific notation.
        NSLog(@"float2: %e", 123400000.0);
        NSLog(@"float3: %E", 123400000.0);

        // For basic string printing use %@.
        NSLog(@"str1: %@", @"\"string\"");

        // To print a representation of a pointer, use %p.
        NSLog(@"pointer: %p", p);

        // When formatting numbers you will often want to control the width and precision of the resulting figure.
        // To specify the width of an integer, use a number after the % in the verb.
        // By default the result will be right-justified and padded with spaces.
        NSLog(@"width1: |%6d|%6d|", 12, 345);

        // You can also specify the width of printed floats,
        // though usually you'll also want to restrict the decimal precision at the same time with the width.precision syntax.
        NSLog(@"width2: |%6.2f|%6.2f|", 1.2, 3.45);

        // To left-justify, use the - flag.
        NSLog(@"width3: |%-6.2f|%-6.2f|", 1.2, 3.45);

        // You may also want to control width when formatting strings,
        // especially to ensure that they align in table-like output.
        // For basic right-justified width.
        NSLog(@"width4: |%6s|%6s|", "foo", "b");

        // To left-justify use the - flag as with numbers.
        NSLog(@"width5: |%-6s|%-6s|", "foo", "b");

        // So far we've seen NSLog, which prints the formatted string to the console.
        // NSString's stringWithFormat: formats and returns a string without printing it anywhere.
        NSString *s = [NSString stringWithFormat:@"stringWithFormat: a %@", @"string"];
        NSLog(@"%@", s);

        // You can format+print to NSFileHandle other than stdout using writeData:.
        NSFileHandle *stderr = [NSFileHandle fileHandleWithStandardError];
        NSString *errorString = [NSString stringWithFormat:@"io: an %@\n", @"error"];
        [stderr writeData:[errorString dataUsingEncoding:NSUTF8StringEncoding]];
    }
    return 0;
}