Implement Seq.iteri2

PatrickMcDonald · latkin · commit d7bcad775ceb · 2014-10-12T16:25:01.000-07:00
commit 459c7a370991f46ae69125cf35966b750998dae3 Merge: e36641b 131b462 Author: latkin <latkin@microsoft.com> Date: Sun Oct 12 16:19:14 2014 -0700 Merge branch 'SeqIteri2' of https://git01.codeplex.com/forks/patrickmcdonald/visualfsharp into PR commit 131b46238ba4552bf57e361d40881352dfe860f0 Author: Patrick McDonald <paddymcdonald@gmail.com> Date: Thu Aug 14 00:36:26 2014 +0100 Fix surface area portable tests commit b27432c38b13d8c68dc2e7bd734b67b9c54bf5f6 Author: Patrick McDonald <paddymcdonald@gmail.com> Date: Thu Aug 7 14:11:10 2014 +0100 Add more Seq.iteri2 test coverage commit a1be9925d3cb54975722d6de140c0f8c54827ab2 Author: Patrick McDonald <paddymcdonald@gmail.com> Date: Tue Aug 5 23:02:18 2014 +0100 Add iteri2 to Seq Module
diff --git a/src/fsharp/FSharp.Core.Unittests/FSharp.Core/Microsoft.FSharp.Collections/SeqModule2.fs b/src/fsharp/FSharp.Core.Unittests/FSharp.Core/Microsoft.FSharp.Collections/SeqModule2.fs
@@ -267,6 +267,49 @@ type SeqModule2() =
         let nullseq:seq<'a> =  null
         CheckThrowsArgumentNullException (fun () -> Seq.iteri funcint nullseq |> ignore)  
         ()
+
+    [<Test>]
+    member this.Iteri2() =
+
+        //seq int
+        let seqint = seq [ 1..3]
+        let cacheint = ref 0
+       
+        let funcint x y z = cacheint := !cacheint + x + y + z
+        Seq.iteri2 funcint seqint seqint
+        Assert.AreEqual(15,!cacheint)
+              
+        //seq str
+        let seqStr = seq ["first";"second"]
+        let cachestr = ref 0
+        let funcstr (x:int) (y:string) (z:string) = cachestr := !cachestr + x + y.Length + z.Length
+        Seq.iteri2 funcstr seqStr seqStr
+         
+        Assert.AreEqual(23,!cachestr)
+        
+        // empty seq
+        let emptyseq = Seq.empty
+        let resultEpt = ref 0
+        Seq.iteri2 (fun x y z -> Assert.Fail()) emptyseq emptyseq 
+
+        // null seq
+        let nullseq:seq<'a> =  null
+        CheckThrowsArgumentNullException (fun () -> Seq.iteri2 funcint nullseq nullseq |> ignore)  
+        
+        // len1 <> len2
+        let shorterSeq = seq { 1..3 }
+        let longerSeq = seq { 2..2..100 }
+
+        let testSeqLengths seq1 seq2 =
+            let cache = ref 0
+            let f x y z = cache := !cache + x + y + z
+            Seq.iteri2 f seq1 seq2
+            !cache
+
+        Assert.AreEqual(21, testSeqLengths shorterSeq longerSeq)
+        Assert.AreEqual(21, testSeqLengths longerSeq shorterSeq)
+
+        ()
         
     [<Test>]
     member this.Length() =
@@ -1309,4 +1352,4 @@ type SeqModule2() =
         
         CheckThrowsArgumentNullException(fun () -> Seq.tryPick funcNull nullSeq |> ignore)
    
-        ()
+        ()
diff --git a/src/fsharp/FSharp.Core.Unittests/SurfaceArea.4.0.fs b/src/fsharp/FSharp.Core.Unittests/SurfaceArea.4.0.fs
@@ -457,6 +457,7 @@ Microsoft.FSharp.Collections.SeqModule: TState Fold2[T1,T2,TState](Microsoft.FSh
 Microsoft.FSharp.Collections.SeqModule: TState Fold[T,TState](Microsoft.FSharp.Core.FSharpFunc`2[TState,Microsoft.FSharp.Core.FSharpFunc`2[T,TState]], TState, System.Collections.Generic.IEnumerable`1[T])
 Microsoft.FSharp.Collections.SeqModule: T[] ToArray[T](System.Collections.Generic.IEnumerable`1[T])
 Microsoft.FSharp.Collections.SeqModule: Void Iterate2[T1,T2](Microsoft.FSharp.Core.FSharpFunc`2[T1,Microsoft.FSharp.Core.FSharpFunc`2[T2,Microsoft.FSharp.Core.Unit]], System.Collections.Generic.IEnumerable`1[T1], System.Collections.Generic.IEnumerable`1[T2])
+Microsoft.FSharp.Collections.SeqModule: Void IterateIndexed2[T1,T2](Microsoft.FSharp.Core.FSharpFunc`2[System.Int32,Microsoft.FSharp.Core.FSharpFunc`2[T1,Microsoft.FSharp.Core.FSharpFunc`2[T2,Microsoft.FSharp.Core.Unit]]], System.Collections.Generic.IEnumerable`1[T1], System.Collections.Generic.IEnumerable`1[T2])
 Microsoft.FSharp.Collections.SeqModule: Void IterateIndexed[T](Microsoft.FSharp.Core.FSharpFunc`2[System.Int32,Microsoft.FSharp.Core.FSharpFunc`2[T,Microsoft.FSharp.Core.Unit]], System.Collections.Generic.IEnumerable`1[T])
 Microsoft.FSharp.Collections.SeqModule: Void Iterate[T](Microsoft.FSharp.Core.FSharpFunc`2[T,Microsoft.FSharp.Core.Unit], System.Collections.Generic.IEnumerable`1[T])
 Microsoft.FSharp.Collections.SetModule: Boolean Contains[T](T, Microsoft.FSharp.Collections.FSharpSet`1[T])
diff --git a/src/fsharp/FSharp.Core.Unittests/SurfaceArea.Portable.fs b/src/fsharp/FSharp.Core.Unittests/SurfaceArea.Portable.fs
@@ -451,6 +451,7 @@ Microsoft.FSharp.Collections.SeqModule: TState Fold2[T1,T2,TState](Microsoft.FSh
 Microsoft.FSharp.Collections.SeqModule: TState Fold[T,TState](Microsoft.FSharp.Core.FSharpFunc`2[TState,Microsoft.FSharp.Core.FSharpFunc`2[T,TState]], TState, System.Collections.Generic.IEnumerable`1[T])
 Microsoft.FSharp.Collections.SeqModule: T[] ToArray[T](System.Collections.Generic.IEnumerable`1[T])
 Microsoft.FSharp.Collections.SeqModule: Void Iterate2[T1,T2](Microsoft.FSharp.Core.FSharpFunc`2[T1,Microsoft.FSharp.Core.FSharpFunc`2[T2,Microsoft.FSharp.Core.Unit]], System.Collections.Generic.IEnumerable`1[T1], System.Collections.Generic.IEnumerable`1[T2])
+Microsoft.FSharp.Collections.SeqModule: Void IterateIndexed2[T1,T2](Microsoft.FSharp.Core.FSharpFunc`2[System.Int32,Microsoft.FSharp.Core.FSharpFunc`2[T1,Microsoft.FSharp.Core.FSharpFunc`2[T2,Microsoft.FSharp.Core.Unit]]], System.Collections.Generic.IEnumerable`1[T1], System.Collections.Generic.IEnumerable`1[T2])
 Microsoft.FSharp.Collections.SeqModule: Void IterateIndexed[T](Microsoft.FSharp.Core.FSharpFunc`2[System.Int32,Microsoft.FSharp.Core.FSharpFunc`2[T,Microsoft.FSharp.Core.Unit]], System.Collections.Generic.IEnumerable`1[T])
 Microsoft.FSharp.Collections.SeqModule: Void Iterate[T](Microsoft.FSharp.Core.FSharpFunc`2[T,Microsoft.FSharp.Core.Unit], System.Collections.Generic.IEnumerable`1[T])
 Microsoft.FSharp.Collections.SetModule: Boolean Contains[T](T, Microsoft.FSharp.Collections.FSharpSet`1[T])
diff --git a/src/fsharp/FSharp.Core/seq.fs b/src/fsharp/FSharp.Core/seq.fs
@@ -931,6 +931,16 @@ namespace Microsoft.FSharp.Collections
             while (e1.MoveNext() && e2.MoveNext()) do
                 f e1.Current e2.Current;
 
+        [<CompiledName("IterateIndexed2")>]
+        let iteri2 f (source1 : seq<_>) (source2 : seq<_>) = 
+            checkNonNull "source1" source1
+            checkNonNull "source2" source2
+            use e1 = source1.GetEnumerator()
+            use e2 = source2.GetEnumerator()
+            let mutable i = 0 
+            while (e1.MoveNext() && e2.MoveNext()) do
+                f i e1.Current e2.Current
+                i <- i + 1
 
         // Build an IEnumerble by wrapping/transforming iterators as they get generated.
         let revamp f (ie : seq<_>) = mkSeq (fun () -> f (ie.GetEnumerator()))
diff --git a/src/fsharp/FSharp.Core/seq.fsi b/src/fsharp/FSharp.Core/seq.fsi
@@ -522,6 +522,18 @@ namespace Microsoft.FSharp.Collections
         [<CompiledName("Iterate2")>]
         val iter2: action:('T1 -> 'T2 -> unit) -> source1:seq<'T1> -> source2:seq<'T2> -> unit
 
+        /// <summary>Applies the given function to two collections simultaneously. If one sequence is shorter than 
+        /// the other then the remaining elements of the longer sequence are ignored. The integer passed to the
+        /// function indicates the index of element.</summary>
+        ///
+        /// <param name="action">A function to apply to each pair of elements from the input sequences along with their index.</param>
+        /// <param name="source1">The first input sequence.</param>
+        /// <param name="source2">The second input sequence.</param>
+        ///
+        /// <exception cref="System.ArgumentNullException">Thrown when either of the input sequences is null.</exception>
+        [<CompiledName("IterateIndexed2")>]
+        val iteri2: action:(int -> 'T1 -> 'T2 -> unit) -> source1:seq<'T1> -> source2:seq<'T2> -> unit
+
         /// <summary>Returns the length of the sequence</summary>
         ///
         /// <param name="source">The input sequence.</param>
