#SOCQ (Syntax for Objective-C Queries)
Bringin' some query love to Objective-C
NSArray
- skip:
- take:
- skip:take:
- where:
- any:
- all:
- groupby:
- distinctObjectsByAddress
- distinct
- select:
- selectKeypaths:
NSDictionary
- where:
- any:
- all:
NSSet
- where:
- any:
- all:
- groupby:
- select:
- selectKeypaths:
##NSArray ####take: - (NSArray*)take:(NSUInteger)inCount;
Returns an array with the specified number of elements from the beginning of the target array.
// Example - Getting the first five elements
NSArray* elements = [people take:5];
####skip: - (NSArray*)skip:(NSUInteger)inCount;
Skips the indicated number of elements in the array and returns an array of the remaining elements.
// Example - skips the first five elements
NSArray* remaining = [people skip:5];
####skip:take: - (NSArray*)skip:(NSUInteger)inSkip take:(NSUInteger)inTake;
Simple convenience method that combines the skip and take methods. Ideal for pagination.
// Example - get elements 6-10
NSArray* remaining = [people skip:5 take:5];
####where: - (NSArray*)where:(BOOL(^)(id obj))check;
Uses the check block on every element in the array to determine if they should be returned in the return array
// Example - find people that are 25 years old
NSArray* 25YearOlds = [people where:^(id obj){ return [obj age] == 25; }];
####any: - (BOOL)any:(BOOL(^)(id obj))check;
Checks every element in the array to see if any of the elements successfully pass the check block. If none pass, return NO, else YES.
// Example - check to see if anyone is under 18
BOOL containsMinors = [people any:^(id obj){ return [obj age] < 18; }];
####all: - (BOOL)all:(BOOL(^)(id obj))check;
Checks every element in the array to see if all of the elements successfully pass the check block. If all elements pass, return YES, else NO.
// Example - check to see if everyone is 25 or over
BOOL everyone25orOver = [people all:^(id obj){ return [obj age] >= 25; }];
####groupby: - (NSDictionary*)groupBy:(id(^)(id obj))groupBlock;
Uses the object returned from the groupBlock block as a key to group the object into a NSDictionary that contains a NSArray with all the objects that returned the same key
// Example - group everyone by their last name
NSDictionary* peopleByFamilyName = [people groupBy:^(id obj){ return [obj lastName]; }];
####distinctObjectsByAddress - (NSArray*)distinctObjectsByAddress;
Does a simple pointer address compare to remove elements that refer to the same object
// Example - remove the exact same elements
NSArray* uniquePeople = [people distinctObjectsByAddress];
####distinct - (NSArray*)distinct;
Uses the class' compare and hash method to remove elements that contain the same value
// Example - remove the exact same elements
NSArray* uniquePeople = [people distinct];
####select: - (NSArray*)select:(id(^)(id originalObject))transform;
Transforms elements in the array into another strongly type object that is returned from the transform block.
// Example - Change people objects into American Class objects
NSArray* americans = [people select:^(id obj){ return [[American alloc] initWithFirstName:[obj firstName]
LastName:[obj lastName]
age:[obj age]] }];
####selectKeypaths: - (NSArray*)selectKeypaths:(NSString*)keypath, ... NS_REQUIRES_NIL_TERMINATION;
Selects properties from the elements in the array using the keypath mechanism. Any number of keypaths maybe specified but the list must be nil terminated. The return value is an array of dictionaries. The dictionary contain the keypaths that were passed in as the parameters as the keys and the valueForKeyPath: as the values.
// Example - Get the four properties we need from the person object
NSArray* americans = [people selectKeypaths:@"firstName",@"lastName",@"parent.firstName",@"age",nil];
##NSDictionary ####where: - (NSDictionary*)where:(BOOL(^)(id key, id value))check;
Uses the check block on every key-object in the dictionary to determine if they should be returned in the return array
// Example - get all the keys and objects where the key is 3 or less characters
NSDictionary* entriesWithKeysOf3OrLess = [peopleGroup where:^(id key, id value){ return [key length] <= 3; }];
####any: - (BOOL)any:(BOOL(^)(id key, id value))check;
Checks every key-object in the dictionary to see if any of the elements successfully pass the check block. If none pass, return NO, else YES.
// Exmaple - finds out if any of the keys are longer than 10 characters
BOOL areAnyKeysLongerThan10 = [peopleGroups any:^(id key, id value){ return [key length] > 10 }];
####all: - (BOOL)all:(BOOL(^)(id key, id value))check;
Checks every key-object in the dictionary to see if all of the elements successfully pass the check block. If all elements pass, return YES, else NO.
// Exmaple - find out if all the keys are strings
BOOL areKeysStrings = [peopleGroups all:^(id key, id value){ return [key class] == [NSString class] }];
##NSSet ####where: - (NSSet*)where:(BOOL(^)(id obj))check;
Uses the check block on every element in the set to determine if they should be returned in the return set
// Example - find people that are 25 years old
NSSet* 25YearOlds = [people where:^(id obj){ return [obj age] == 25; }];
####any: - (BOOL)any:(BOOL(^)(id obj))check;
Checks every element in the set to see if any of the elements successfully pass the check block. If none pass, return NO, else YES.
// Example - check to see if anyone is under 18
BOOL containsMinors = [people any:^(id obj){ return [obj age] < 18; }];
####all: - (BOOL)all:(BOOL(^)(id obj))check;
Checks every element in the set to see if all of the elements successfully pass the check block. If all elements pass, return YES, else NO.
// Example - check to see if everyone is 25 or over
BOOL everyone25orOver = [people all:^(id obj){ return [obj age] >= 25; }];
####groupby: - (NSDictionary*)groupBy:(id(^)(id obj))groupBlock;
Uses the object returned from the groupBlock block as a key to group the object into a NSDictionary that contains a NSSet with all the objects that returned the same key
// Example - group everyone by their last name
NSDictionary* peopleByFamilyName = [people groupBy:^(id obj){ return [obj lastName]; }];
####select: - (NSSet*)select:(id(^)(id originalObject))transform;
Transforms elements in the set into another strongly type object that is returned from the transform block.
// Example - Change people objects into American Class objects
NSSet* americans = [people select:^(id obj){ return [[American alloc] initWithFirstName:[obj firstName]
LastName:[obj lastName]
age:[obj age]] }];
####selectKeypaths: - (NSSet*)selectKeypaths:(NSString*)keypath, ... NS_REQUIRES_NIL_TERMINATION;
Selects properties from the elements in the set using the keypath mechanism. Any number of keypaths maybe specified but the list must be nil terminated. The return value is an set of dictionaries. The dictionary contain the keypaths that were passed in as the parameters as the keys and the valueForKeyPath: as the values.
// Example - Get the four properties we need from the person object
NSSet* americans = [people selectKeypaths:@"firstName",@"lastName",@"parent.firstName",@"age",nil];