Feature/evented fns (#70)

* Evented addEvent

* exec mapE listen

Co-authored-by: Radu Popovici <[email protected]>

src/Core/NBB.Core.Evented.FSharp/Evented.fs

@@ -2,6 +2,7 @@
 
 type Evented<'a, 'e> = Evented of payload:'a * events:'e list
 
+[<RequireQualifiedAccess>]
 module Evented = 
     let map func (Evented(value, events)) = Evented(func value, events)
 
@@ -17,6 +18,10 @@ module Evented =
 
     let lift2 f = map f >> apply
 
+    let run (Evented(value, events): Evented<'a, 'e>) = (value, events)
+    let exec (Evented(_value, events): Evented<'a, 'e>) = events
+    let mapE (func:'e->'f) (Evented(value, events): Evented<'a,'e>) = Evented(value, events |> List.map func)
+
 type Evented<'a, 'e> with
     static member Map (x, f) = Evented.map  f x
     static member Return (x) = Evented.return' x
@@ -32,14 +37,17 @@ module EventedBuilder =
         member _.Zero() = Evented.return' ()
 
 [<AutoOpen>]
-module Events =
+module EventedExtensions =
     let evented = new EventedBuilder.EventedBuilder()
 
     let (<!>) = Evented.map
     let (<*>) = Evented.apply
     let (>>=) evented func = Evented.bind func evented
     let (>=>) = Evented.composeK
 
+    let addEvent (ev:'e) = Evented((),[ev])
+    let listen (Evented (value, events): Evented<'a,'e>) = Evented((value,events),events)
+
 [<RequireQualifiedAccess>]
 module List =
     let traverseEvented f list =

test/UnitTests/Core/NBB.Core.Evented.FSharp.Tests/NBB.Core.Evented.FSharp.Tests.fsproj

@@ -9,6 +9,7 @@
 
   <ItemGroup>
     <Compile Include="Sample.fs" />
+    <Compile Include="Sample2.fs" />
     <Compile Include="Tests.fs" />
     <Compile Include="Program.fs" />
   </ItemGroup>

test/UnitTests/Core/NBB.Core.Evented.FSharp.Tests/Sample.fs

@@ -1,4 +1,4 @@
-module Sample
+namespace NBB.Core.Evented.FSharp.Tests
 
 open NBB.Core.Evented.FSharp
 open FSharpPlus
@@ -10,7 +10,6 @@ module Domain =
         | Updated
 
     let create x =  Evented(AggRoot x, [Added])
-
     let update (x:AggRoot) = Evented(x, [Updated])
     let increment (AggRoot x) = AggRoot (x + 1)
 

test/UnitTests/Core/NBB.Core.Evented.FSharp.Tests/Sample2.fs

@@ -0,0 +1,31 @@
+namespace NBB.Core.Evented.FSharp.Tests
+
+open NBB.Core.Evented.FSharp
+
+module Sample2 =
+    type Payment = {
+        Id: int
+        Amount: decimal
+        Cancelled: bool
+    }
+
+    type DomainEvent = 
+        | Added of Id:int * Amount:decimal
+        | Cancelled of Id:int
+
+    let create (id,amount) = 
+        evented{
+            let payment = {Id=id; Amount=amount; Cancelled=false}
+            do! addEvent <| Added(id,amount)
+            return payment
+        }
+
+    let cancell payment = 
+        evented{
+            let payment' = {payment with Cancelled=true}
+            do! addEvent <| Cancelled payment.Id
+            return payment'
+        }
+
+    let createCancelled = create >=> cancell
+