OCTotallyLazy - Functional extensions to Objective-C.
OCTotallyLazy is a framework that adds functional behaviour to Objective C collection objects, as well as a lazy collection object called Sequence. It's a partial port of Dan Bodart's TotallyLazy Java library, available here: http://code.google.com/p/totallylazy/
The best place to look for full behaviour is in the test classes for now, checkout https://github.com/stuartervine/OCTotallyLazy/blob/master/src/test-unit/SequenceTest.m
Importing OCTotallyLazy in your code.
import <OCTotallyLazy/OCTotallyLazy.h>
What's available?
NSArray
drop:
dropWhile:
filter:
find:
flatMap:
flatten
fold: with:
foreach:
isEmpty
groupBy:
grouped:
head
headOption
join:
map:
mapWithIndex:
merge:
partition:
reduce:
reverse
splitAt:
splitOn:
splitWhen:
tail
take:
takeWhile:
takeRight:
toString
toString:
toString: separator: end:
zip:
zipWithIndex
asSequence
asSet
asDictionary
Some basic examples.
Mapping (Sequence, NSArray, partially on NSSet, NSDictionary)
[sequence(@"one", @"two", @"three", nil) map:^(NSString *item){
return [item uppercaseString];
}]
// returns sequence(@"ONE", @"TWO", @"THREE", nil)
[@[@"one", @[@"two"], @"three"] flatMap:^(NSString *item){
return [item uppercaseString];
}];
// returns array(@"ONE", @"TWO", @"THREE", nil)
Filtering (Sequence, NSArray, NSSet, NSDictionary)
[sequence(@"1", @"12", @"123", @"1234", nil) filter:^(NSString *item){
return item.length > 2;
}]
//returns sequence(@"123", @"1234", nil)
Options
[Option option:@"something"];
//Outputs [Some some:@"something"];
[Option option:nil];
//Outputs [None none];
[[Option option:@"something"] map:^(NSString *item){
return [item uppercaseString];
}];
//Outputs [Some some:@"SOMETHING"];
[Option option:nil] map:^(NSString *item){
return [item uppercaseString];
}];
//Outputs [None none];
Shorthand, for the totally lazy
The above examples are still quite noisy. There is shorthand syntax available too. Include the following above the framework import.
#define TL_SHORTHAND
#define TL_LAMBDA
#define TL_LAMBDA_SHORTHAND
import <OCTotallyLazy/OCTotallyLazy.h>
Then you can do fun stuff such as:
[sequence(num(1), num(2), num(3), nil) find:not(eqTo(num(1))]; //outputs [Some some:num(2)];
Lambda craziness
Verbose:
[sequence(@"bob", @"fred", @"wilma", nil) map:^(NSString *item){return [item uppercaseString];}] //outputs sequence(@"BOB", @"FRED", @"WILMA", nil)
A bit more sane:
[sequence(@"bob", @"fred", @"wilma", nil) map:lambda(s, [s uppercaseString])] //outputs sequence(@"BOB", @"FRED", @"WILMA", nil)
A bit mental (but a bit like scala):
[sequence(@"bob", @"fred", @"wilma", nil) map:_([_ uppercaseString])] //outputs sequence(@"BOB", @"FRED", @"WILMA", nil)
I like it - how do I get it?
So I'm a bit fed up with using 'libraries' that say, just include our source code in your project, or attach our xcode project to your project. So to use this:
- Clone the repo.
- Run <CHECKOUT_DIR>/build.sh test //optional, but if it fails shout at me!
- Run <CHECKOUT_DIR>/build.sh release
- Copy <CHECKOUT_DIR>/build/Release-iphoneos/OCTotallyLazy.framework to your external libraries folder.
- Import the framework to your project.
- Jobsa good 'un.
Or if you're using CocoaPods, add the following line to your Podfile
pod 'OCTotallyLazy'
OCTotallyLazy is also Carthage compatible now, just add the following to your Cartfile:
github "stuartervine/OCTotallyLazy" >= 2.0.0
