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comparison Main/jungle-main/util/DefaultEither.cs @ 34:a79781723862

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Add bind function to Either.cs Rewrite use bind.
author Kazuma Takeda
date Tue, 07 Feb 2017 20:50:50 +0900
parents 56de71ae6f7e
children f2ea780b3e80
comparison
equal deleted inserted replaced
33:56de71ae6f7e 34:a79781723862
1  1 
2 public class DefaultEither<A,B> : Either<A,B> { 2 public class DefaultEither<A,B> : Either<A,B> {
3 private A theA; 3 private A theA;
4 private B theB; 4 private B theB;
5
6 public void SetB (B b) {
7 this.theB = b;
8 }
9
10 public void SetA (A a) {
11 this.theA = a;
12 }
13
14 public delegate B Func (B b);
15 5
16 public DefaultEither(A _theA, B _theB){ 6 public DefaultEither(A _theA, B _theB){
17 theA = _theA; 7 theA = _theA;
18 theB = _theB; 8 theB = _theB;
19 } 9 }
49 public bool isB() 39 public bool isB()
50 { 40 {
51 return theB != null; 41 return theB != null;
52 } 42 }
53 43
54 public Either<A, B> fmap(System.Func<B, B> f, Either<A,B> e) { 44 public Either<A, B> fmap(System.Func<B, B> f) {
55 if (e.isA ()) { 45 if (isA ()) {
56 return e; 46 return this;
57 } 47 }
58 this.SetB (f (e.b())); 48 return newB(f(b()));
59 return this;
60 } 49 }
61 50
51 public Either<A, B> bind (System.Func<B, Either<A, B>> f) {
52 if (isA ()) {
53 return this;
54 }
55
56 return f (b ());
57 }
62 } 58 }