Use distinctBy instead of noRepeats (#9104)

* Use distinctBy instead of noRepeats

* Use distinctBy instead of noRepeats

src/fsharp/InnerLambdasToTopLevelFuncs.fs

@@ -706,7 +706,7 @@ let FlatEnvPacks g fclassM topValS declist (reqdItemsMap: Zmap<BindingGroupShari
 
        // determine vals(env) - transclosure
        let vals = env.ReqdVals @ List.collect valsSubEnvFor env.ReqdSubEnvs  // list, with repeats
-       let vals = List.noRepeats valOrder vals                        // noRepeats
+       let vals = vals |> List.distinctBy (fun v -> v.Stamp)
 
        // Remove genuinely toplevel, no need to close over these
        let vals = vals |> List.filter (IsMandatoryTopLevel >> not)

src/fsharp/MethodCalls.fs

@@ -457,9 +457,9 @@ type CalledMeth<'T>
                               | _ -> 
                                   Choice2Of2(arg))
 
-            let names = namedCallerArgs |> List.map (fun (CallerNamedArg(nm, _)) -> nm.idText) 
+            let names = namedCallerArgs |> List.distinctBy (fun (CallerNamedArg(nm, _)) -> nm.idText) 
 
-            if (List.noRepeats String.order names).Length <> namedCallerArgs.Length then
+            if names.Length <> namedCallerArgs.Length then
                 errorR(Error(FSComp.SR.typrelNamedArgumentHasBeenAssignedMoreThenOnce(), m))
                 
             let argSet = { UnnamedCalledArgs=unnamedCalledArgs; UnnamedCallerArgs=unnamedCallerArgs; ParamArrayCalledArgOpt=paramArrayCalledArgOpt; ParamArrayCallerArgs=paramArrayCallerArgs; AssignedNamedArgs=assignedNamedArgs }

src/fsharp/lib.fs

@@ -267,11 +267,6 @@ let mapTriple (f1, f2, f3) (a1, a2, a3) = (f1 a1, f2 a2, f3 a3)
 let mapQuadruple (f1, f2, f3, f4) (a1, a2, a3, a4) = (f1 a1, f2 a2, f3 a3, f4 a4)
 let fmap2Of2 f z (a1, a2) = let z, a2 = f z a2 in z, (a1, a2)
 
-module List = 
-    let noRepeats xOrder xs =
-        let s = Zset.addList xs (Zset.empty xOrder) // build set 
-        Zset.elements s // get elements... no repeats
-
 //---------------------------------------------------------------------------
 // Zmap rebinds
 //-------------------------------------------------------------------------