List Multipartition

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// Partitions a list into a map of key->List<T> based on the 
// key returned by the call to discriminatorFunc
// Note that lists are in reversed order to the input...
let ListPartition (discriminatorFunc : 'V -> 'K) list = 
    let rec part (map:System.Collections.Generic.Dictionary<'K,'V list>) listTail =
        match listTail with
        | [] -> map
        | x :: tail -> let key = discriminatorFunc x
                       let res,list =  map.TryGetValue(key)
                       match res with
                       | false -> map.Add(key,[x])
                       | true -> map.[key] <- x :: list
                       part map tail

    part (new System.Collections.Generic.Dictionary<'K,'V list>()) list

val ListPartition : discriminatorFunc:('V -> 'K) -> list:'V list -> System.Collections.Generic.Dictionary<'K,'V list> (requires equality)

Full name: Script.ListPartition

val discriminatorFunc : ('V -> 'K) (requires equality)

Multiple items
val list : 'V list

--------------------
type 'T list = List<'T>

Full name: Microsoft.FSharp.Collections.list<_>

val part : (System.Collections.Generic.Dictionary<'K,'V list> -> 'V list -> System.Collections.Generic.Dictionary<'K,'V list>) (requires equality)

val map : System.Collections.Generic.Dictionary<'K,'V list> (requires equality)

namespace System

namespace System.Collections

namespace System.Collections.Generic

Multiple items
type Dictionary<'TKey,'TValue> =
  new : unit -> Dictionary<'TKey, 'TValue> + 5 overloads
  member Add : key:'TKey * value:'TValue -> unit
  member Clear : unit -> unit
  member Comparer : IEqualityComparer<'TKey>
  member ContainsKey : key:'TKey -> bool
  member ContainsValue : value:'TValue -> bool
  member Count : int
  member GetEnumerator : unit -> Enumerator<'TKey, 'TValue>
  member GetObjectData : info:SerializationInfo * context:StreamingContext -> unit
  member Item : 'TKey -> 'TValue with get, set
  ...
  nested type Enumerator
  nested type KeyCollection
  nested type ValueCollection

Full name: System.Collections.Generic.Dictionary<_,_>

--------------------
System.Collections.Generic.Dictionary() : unit
System.Collections.Generic.Dictionary(capacity: int) : unit
System.Collections.Generic.Dictionary(comparer: System.Collections.Generic.IEqualityComparer<'TKey>) : unit
System.Collections.Generic.Dictionary(dictionary: System.Collections.Generic.IDictionary<'TKey,'TValue>) : unit
System.Collections.Generic.Dictionary(capacity: int, comparer: System.Collections.Generic.IEqualityComparer<'TKey>) : unit
System.Collections.Generic.Dictionary(dictionary: System.Collections.Generic.IDictionary<'TKey,'TValue>, comparer: System.Collections.Generic.IEqualityComparer<'TKey>) : unit

val listTail : 'V list

val x : 'V

val tail : 'V list

val key : 'K (requires equality)

val res : bool

System.Collections.Generic.Dictionary.TryGetValue(key: 'K, value: byref<'V list>) : bool

System.Collections.Generic.Dictionary.Add(key: 'K, value: 'V list) : unit