com.aol.cyclops.control

Interface Reader<T,R>

Type Parameters:

T - Current input type of Function

R - Current return type of Function

All Superinterfaces:

java.util.function.Function<T,R>, Functor<R>

All Known Implementing Classes:

FluentFunctions.FluentFunction

public interface Reader<T,R>
extends java.util.function.Function<T,R>, Functor<R>

An interface that represents the Reader monad A technique for functional dependency injection. Functions rather than values are manipulated and dependencies injected into Functions to execute them. Dependency injection using the Reader Monad in Java 8

  
 For comprehension with the Reader Monad, using curried syntax :-
  
 import com.aol.cyclops.control.For;
 
 Reader<UserRepository,Integer> res =  For.reader(depth1("bob"))
                                            .reader(a->depth2("bob"))
                                            .reader(a->b->depth3("bob"))
                                            .reader(a->b->c->depth3("bob"))
                                            .reader(a->b->c->d->depth4("bob"))
                                            .reader(a->b->c->d->e->depth5("bob"))
                                            .reader(a->b->c->d->e->f->depth5("bob"))
                                            .reader(a->b->c->d->e->f->g->depth6("bob"))
                                            .yield(a->b->c->d->e->f->g->h->a+b+c+d+e+f+g+h).unwrap();
   res.apply(new UserRepositoryImpl())
   //29
   private Reader<UserRepository,Integer> depth8(String name){
        return repo->depth7(name).apply(repo)+1;
   }
 
 
 
 

Method Summary

Modifier and Type	Method and Description
default AnyM<R>	anyM()
default <R1> Reader<T,R1>	flatMap(java.util.function.Function<? super R,? extends Reader<T,R1>> f) FlatMap this Reader by applying the prodived function and unnesting to a single Reader
default <R1> Reader<T,R1>	map(java.util.function.Function<? super R,? extends R1> f2) Transform this functor using the supplied transformation function

Methods inherited from interface java.util.function.Function

andThen, apply, compose, identity

Methods inherited from interface com.aol.cyclops.types.Functor

cast, patternMatch, peek, trampoline

Method Detail

map

default <R1> Reader<T,R1> map(java.util.function.Function<? super R,? extends R1> f2)

Description copied from interface: Functor

Transform this functor using the supplied transformation function

  
  
  
    of(1,2,3).map(i->i*2)
    
    //[2,4,6]
  
 
 

Specified by:

map in interface Functor<R>

Parameters:

f2 - Transformation function

Returns:

Transformed Functor

flatMap

default <R1> Reader<T,R1> flatMap(java.util.function.Function<? super R,? extends Reader<T,R1>> f)

FlatMap this Reader by applying the prodived function and unnesting to a single Reader

Parameters:

f - Transformation function to be flattened

Returns:

Transformed Reader

anyM

default AnyM<R> anyM()

Returns:

This Reader instance wrapped inside an AnyM (monad wrapper)