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gustygusty
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Allow unioning them
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‎src/FSharpPlus/Extensions/Dict.fs‎

Lines changed: 120 additions & 45 deletions
Original file line numberDiff line numberDiff line change
@@ -129,13 +129,128 @@ module Dict =
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dct2.Add (k, vy)
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dct1 :> IDictionary<'Key, 'T1>, dct2 :> IDictionary<'Key, 'T2>
131131

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/// <summary>Creates a conceptually infinite dictionay containing the same value for all possible keys.</summary>
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/// <param name="source">The value for all possible keys.</param>
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let initInfinite<'TKey,'TValue> (source: 'TValue) : IDictionary<'TKey,'TValue> =
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let icollection value =
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{
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new ICollection<'t> with
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member __.Contains (item: 't) = obj.ReferenceEquals (item, value)
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member __.GetEnumerator () = (Seq.initInfinite (fun _ -> value)).GetEnumerator () :> System.Collections.IEnumerator
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member __.GetEnumerator () = (Seq.initInfinite (fun _ -> value)).GetEnumerator () : IEnumerator<'t>
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member __.IsReadOnly = true
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member __.Add (_item: 't) : unit = raise (System.NotImplementedException())
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member __.Clear () : unit = raise (System.NotImplementedException())
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member __.CopyTo (_array: 't [], _arrayIndex: int) : unit = raise (System.NotImplementedException())
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member __.Count : int = -1
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member __.Remove (_item: 't): bool = raise (System.NotImplementedException())
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}
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{
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new IDictionary<'TKey,'TValue> with
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member __.TryGetValue (_key: 'TKey, value: byref<'TValue>) = value <- source; true
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member __.Count = -1
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member __.ContainsKey (_key: 'TKey) = true
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member __.Contains (item: KeyValuePair<'TKey,'TValue>) = obj.ReferenceEquals (item.Value, source)
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member __.GetEnumerator () = invalidOp "Key set is potentially infinite." : System.Collections.IEnumerator
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member __.GetEnumerator () = invalidOp "Key set is potentially infinite." : IEnumerator<KeyValuePair<'TKey,'TValue>>
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member __.IsReadOnly = true
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member __.Values = icollection source
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member __.Item
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with get (_key: 'TKey) : 'TValue = source
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and set (_key: 'TKey) (_: 'TValue) : unit = raise (System.NotImplementedException())
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member __.Add (_key: 'TKey, _value: 'TValue) : unit = raise (System.NotImplementedException())
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member __.Add (_item: KeyValuePair<'TKey,'TValue>) : unit = raise (System.NotImplementedException())
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member __.Clear () : unit = raise (System.NotImplementedException())
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member __.CopyTo (_arr: KeyValuePair<'TKey,'TValue> [], _arrayIndex: int) : unit = raise (System.NotImplementedException())
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member __.Keys : ICollection<'TKey> = raise (System.NotImplementedException())
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member __.Remove (_key: 'TKey) : bool = raise (System.NotImplementedException())
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member __.Remove (_item: KeyValuePair<'TKey,'TValue>) : bool = raise (System.NotImplementedException())
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}
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let initHybrid<'TKey,'TValue> (konst: 'TValue) (source: IDictionary<'TKey,'TValue>) : IDictionary<'TKey,'TValue> =
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let icollection (konst: 'TValue) (source: IDictionary<'TKey,'TValue>) =
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{
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new ICollection<'t> with
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member __.Contains (item: 't) = source.Values.Contains item || obj.ReferenceEquals (item, konst)
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member __.GetEnumerator () = (seq { yield! source.Values; yield! (Seq.initInfinite (fun _ -> konst))}).GetEnumerator () :> System.Collections.IEnumerator
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member __.GetEnumerator () = (seq { yield! source.Values; yield! (Seq.initInfinite (fun _ -> konst))}).GetEnumerator () : IEnumerator<'t>
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member __.IsReadOnly = true
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member __.Add (_item: 't) : unit = raise (System.NotImplementedException())
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member __.Clear () : unit = raise (System.NotImplementedException())
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member __.CopyTo (_array: 't [], _arrayIndex: int) : unit = raise (System.NotImplementedException())
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member __.Count : int = -source.Count-1
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member __.Remove (_item: 't): bool = raise (System.NotImplementedException())
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}
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{
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new IDictionary<'TKey,'TValue> with
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member __.TryGetValue (key: 'TKey, value: byref<'TValue>) =
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match source.TryGetValue key with
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| true, v -> value <- v
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| _ -> value <- konst
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true
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member __.Count = -source.Count-1
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member __.ContainsKey (_key: 'TKey) = true
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member __.Contains (item: KeyValuePair<'TKey,'TValue>) =
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match source.TryGetValue item.Key with
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| true, v -> obj.ReferenceEquals (item.Value, v)
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| _ -> obj.ReferenceEquals (item.Value, konst)
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member __.GetEnumerator () = source.GetEnumerator () : System.Collections.IEnumerator
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member __.GetEnumerator () = source.GetEnumerator () : IEnumerator<KeyValuePair<'TKey,'TValue>>
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member __.IsReadOnly = true
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member __.Values = icollection konst source
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member __.Item
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with get (key: 'TKey) : 'TValue = match source.TryGetValue key with (true, v) -> v | _ -> konst
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and set (_key: 'TKey) (_: 'TValue) : unit = raise (System.NotImplementedException())
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member __.Add (_key: 'TKey, _value: 'TValue) : unit = raise (System.NotImplementedException())
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member __.Add (_item: KeyValuePair<'TKey,'TValue>) : unit = raise (System.NotImplementedException())
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member __.Clear () : unit = raise (System.NotImplementedException())
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member __.CopyTo (_arr: KeyValuePair<'TKey,'TValue> [], _arrayIndex: int) : unit = raise (System.NotImplementedException())
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member __.Keys : ICollection<'TKey> = raise (System.NotImplementedException())
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member __.Remove (_key: 'TKey) : bool = raise (System.NotImplementedException())
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member __.Remove (_item: KeyValuePair<'TKey,'TValue>) : bool = raise (System.NotImplementedException())
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}
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132221
/// Returns the union of two dictionaries, using the combiner function for duplicate keys.
133222
let unionWith combiner (source1: IDictionary<'Key, 'Value>) (source2: IDictionary<'Key, 'Value>) =
134-
let d = Dictionary<'Key,'Value> ()
135-
let f = OptimizedClosures.FSharpFunc<_,_,_>.Adapt combiner
136-
for KeyValue(k, v ) in source1 do d.[k] <- v
137-
for KeyValue(k, v') in source2 do d.[k] <- match d.TryGetValue k with true, v -> f.Invoke (v, v') | _ -> v'
138-
d :> IDictionary<'Key,'Value>
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let combine () =
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let d = Dictionary<'Key,'Value> ()
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let f = OptimizedClosures.FSharpFunc<_,_,_>.Adapt combiner
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for KeyValue(k, v ) in source1 do d.[k] <- v
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for KeyValue(k, v') in source2 do d.[k] <- match d.TryGetValue k with true, v -> f.Invoke (v, v') | _ -> v'
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d :> IDictionary<'Key,'Value>
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let combineWithKonst source konst =
230+
let d = Dictionary<'Key,'Value> ()
231+
for KeyValue(k, v) in source do d.[k] <- combiner v konst
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d :> IDictionary<'Key,'Value>
233+
let combineKonstWith konst source =
234+
let d = Dictionary<'Key,'Value> ()
235+
for KeyValue(k, v) in source do d.[k] <- combiner konst v
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d :> IDictionary<'Key,'Value>
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match source1.Count, source2.Count with
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| -1, -1 ->
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initInfinite (
240+
combiner
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(source1[Unchecked.defaultof<'Key>])
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(source2[Unchecked.defaultof<'Key>]))
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| -1, 0 -> source1
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| 0, -1 -> source2
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| -1, x when x < -1 -> initHybrid (combiner (source1[Unchecked.defaultof<'Key>]) (source2[Unchecked.defaultof<'Key>])) (combineKonstWith (source1[Unchecked.defaultof<'Key>]) source2)
246+
| x, -1 when x < -1 -> initHybrid (combiner (source1[Unchecked.defaultof<'Key>]) (source2[Unchecked.defaultof<'Key>])) (combineWithKonst source1 (source2[Unchecked.defaultof<'Key>]))
247+
// Note: this is horrible and Unchecked.defaultof<'Key> is 0 for int keys, so it might not return the default value.
248+
// All this hints that a specific (named) class is needed, something like DictWithDefaultValue<'Key, 'Value> then type tests can be added before reading the defaultValue property.
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| x, y when x < -1 && y < -1 -> initHybrid (combiner (source1[Unchecked.defaultof<'Key>]) (source2[Unchecked.defaultof<'Key>])) (combine())
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| -1, _ -> combineKonstWith (source1[Unchecked.defaultof<'Key>]) source2 |> initHybrid (source1[Unchecked.defaultof<'Key>])
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| _, -1 -> combineWithKonst source1 (source2[Unchecked.defaultof<'Key>]) |> initHybrid (source2[Unchecked.defaultof<'Key>])
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| _, _ -> combine()
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139254

140255
#if !FABLE_COMPILER
141256
///Returns the union of two maps, preferring values from the first in case of duplicate keys.
@@ -179,44 +294,4 @@ module Dict =
179294
| None -> ()
180295
dct :> IDictionary<'Key, 'U>
181296

182-
/// <summary>Creates a conceptually infinite dictionay containing the same value for all possible keys.</summary>
183-
/// <param name="source">The value for all possible keys.</param>
184-
let initInfinite<'TKey,'TValue> (source: 'TValue) : IDictionary<'TKey,'TValue> =
185-
186-
let icollection value =
187-
{
188-
new ICollection<'t> with
189-
member __.Contains (item: 't) = obj.ReferenceEquals (item, value)
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member __.GetEnumerator () = (Seq.initInfinite (fun _ -> value)).GetEnumerator () :> System.Collections.IEnumerator
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member __.GetEnumerator () = (Seq.initInfinite (fun _ -> value)).GetEnumerator () : IEnumerator<'t>
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member __.IsReadOnly = true
193-
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member __.Add (_item: 't) : unit = raise (System.NotImplementedException())
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member __.Clear () : unit = raise (System.NotImplementedException())
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member __.CopyTo (_array: 't [], _arrayIndex: int) : unit = raise (System.NotImplementedException())
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member __.Count : int = raise (System.NotImplementedException())
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member __.Remove (_item: 't): bool = raise (System.NotImplementedException())
199-
}
200-
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{
202-
new IDictionary<'TKey,'TValue> with
203-
member __.TryGetValue (_key: 'TKey, value: byref<'TValue>) = value <- source; true
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member __.Count = System.Int32.MaxValue
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member __.ContainsKey (_key: 'TKey) = true
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member __.Contains (item: KeyValuePair<'TKey,'TValue>) = obj.ReferenceEquals (item.Value, source)
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member __.GetEnumerator () = invalidOp "Key set is potentially infinite." : System.Collections.IEnumerator
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member __.GetEnumerator () = invalidOp "Key set is potentially infinite." : IEnumerator<KeyValuePair<'TKey,'TValue>>
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member __.IsReadOnly = true
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member __.Values = icollection source
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member __.Item
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with get (_key: 'TKey) : 'TValue = source
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and set (_key: 'TKey) (_: 'TValue) : unit = raise (System.NotImplementedException())
214297

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member __.Add (_key: 'TKey, _value: 'TValue) : unit = raise (System.NotImplementedException())
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member __.Add (_item: KeyValuePair<'TKey,'TValue>) : unit = raise (System.NotImplementedException())
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member __.Clear () : unit = raise (System.NotImplementedException())
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member __.CopyTo (_arr: KeyValuePair<'TKey,'TValue> [], _arrayIndex: int) : unit = raise (System.NotImplementedException())
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member __.Keys : ICollection<'TKey> = raise (System.NotImplementedException())
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member __.Remove (_key: 'TKey) : bool = raise (System.NotImplementedException())
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member __.Remove (_item: KeyValuePair<'TKey,'TValue>) : bool = raise (System.NotImplementedException())
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}

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