Sorting a collection of people by NSPersonNameComponents

README.m

```obj-c

    /**
     *  Sorting by NSPersonNameComponents
     *  Assuming you have a collection of people objects, each with a property pointing to a 
     *  (populated) NSPersonNameComponents object...
     **/
    
    @interface MyPeepsClass : HashableCodeableArchivableSuperClass
        @property (nonatomic,strong) NSPersonNameComponents *nameComponents;
    @end
    
    NSArray<MyPeepsClass *>*people = @[person1,
                                       person2,
                                       person3,
                                        ....
                                       personN
                                      ];
    /**
        This is how you can sort them (the people).
        Create a catagory on NSPersonNameComponents that implements compare: ...
        Then .... sort!
     **/
    
    NSString *componentsKey = NSStringFromSelector(nameComponents);
    NSSortDescriptor *sortByComponents = [NSSortDescriptor sortDescriptorWithKey:componentsKey ascending:YES]
    
    NSArray *sorted = [people sortedArrayUsingDescriptors:@[sortByComponents]];

    
                       
   

NSPersonNameComponents+Sort.h

#import <Foundation/Foundation.h>

@interface NSPersonNameComponents(Sort)

- (NSComparisonResult)compare:(NSPersonNameComponents *)other;
- (NSComparisonResult)compare:(NSPersonNameComponents *)other options:(NSStringCompareOptions)mask;

@end

NSPersonNameComponents+Sort.m

#import "NSPersonNameComponents+Sort.h"
#import "TXLTypeCheck.h"

@implementation NSPersonNameComponents(Sort)

- (NSComparisonResult)compare:(NSPersonNameComponents *)other
{
    other = TXLValueIfClass(NSPersonNameComponents, other);
    if (!other)
        return NSOrderedDescending;
    
    NSArray *keys = @[NSStringFromSelector(@selector(familyName)),
                      NSStringFromSelector(@selector(givenName)),
                      NSStringFromSelector(@selector(nameSuffix)),
                      NSStringFromSelector(@selector(namePrefix)),
                      ];
    
    NSComparisonResult result = NSOrderedSame;
    for (NSString *key in keys)
    {
        NSString *mine = (NSString *)([[self valueForKey:key] isKindOfClass:NSString.class]) ? [self valueForKey:key] : nil;
        NSString *theirs = (NSString *)([[other valueForKey:key] isKindOfClass:NSString.class]) ? [other valueForKey:key] : nil;
        if (mine && !theirs)
            return NSOrderedDescending;
        if (!mine && theirs)
            return NSOrderedAscending;
        if (mine)
            result = [mine compare:theirs];
        else if (theirs)
            result = NSOrderedAscending;
        if (result != NSOrderedSame)
            return result;
    }
    return result;
}

- (NSComparisonResult)compare:(NSPersonNameComponents *)other options:(NSStringCompareOptions)mask
{
    
    other = (NSPersonNameComponents *)([other isKindOfClass:NSPersonNameComponents.class]) ? other : nil;
    if (!other)
        return NSOrderedDescending;
    
    NSArray *keys = @[NSStringFromSelector(@selector(familyName)),
                      NSStringFromSelector(@selector(givenName)),
                      NSStringFromSelector(@selector(nameSuffix)),
                      NSStringFromSelector(@selector(namePrefix)),
                      ];
    
    NSComparisonResult result = NSOrderedSame;
    for (NSString *key in keys)
    {
        NSString *mine = (NSString *)([[self valueForKey:key] isKindOfClass:NSString.class]) ? [self valueForKey:key] : nil;
        if (!mine.length)
            mine = nil;
        NSString *theirs = (NSString *)([[other valueForKey:key] isKindOfClass:NSString.class]) ? [other valueForKey:key] : nil;
        if (!theirs.length)
            theirs = nil;
        if (mine && !theirs)
            return NSOrderedDescending;
        if (!mine && theirs)
            return NSOrderedAscending;
        if (mine)
            result = [mine compare:theirs options:mask];
        else if (theirs)
            result = NSOrderedAscending;
        if (result != NSOrderedSame)
            return result;
    }
    return result;
}

@end