Extract some utilities from http-client branch (#260)

ConsumePlugin/Args.fs

@@ -195,3 +195,43 @@ type ManyLongForms =
 type private IrrelevantDu =
     | Foo
     | Bar
+
+[<ArgParser true>]
+type FlagsIntoPositionalArgs =
+    {
+        A : string
+        [<PositionalArgs true>]
+        GrabEverything : string list
+    }
+
+[<ArgParser true>]
+type FlagsIntoPositionalArgsChoice =
+    {
+        A : string
+        [<PositionalArgs true>]
+        GrabEverything : Choice<string, string> list
+    }
+
+[<ArgParser true>]
+type FlagsIntoPositionalArgsInt =
+    {
+        A : string
+        [<PositionalArgs true>]
+        GrabEverything : int list
+    }
+
+[<ArgParser true>]
+type FlagsIntoPositionalArgsIntChoice =
+    {
+        A : string
+        [<PositionalArgs true>]
+        GrabEverything : Choice<int, int> list
+    }
+
+[<ArgParser true>]
+type FlagsIntoPositionalArgs' =
+    {
+        A : string
+        [<PositionalArgs false>]
+        DontGrabEverything : string list
+    }

WoofWare.Myriad.Plugins.Attributes/ArgParserAttributes.fs

@@ -19,9 +19,22 @@ type ArgParserAttribute (isExtensionMethod : bool) =
 
 /// Attribute indicating that this field shall accumulate all unmatched args,
 /// as well as any that appear after a bare `--`.
-type PositionalArgsAttribute () =
+///
+/// Set `includeFlagLike = true` to include args that begin `--` in the
+/// positional args.
+/// (By default, `includeFlagLike = false` and we throw when encountering
+/// an argument which looks like a flag but which we don't recognise.)
+/// We will still interpret `--help` as requesting help, unless it comes after
+/// a standalone `--` separator.
+type PositionalArgsAttribute (includeFlagLike : bool) =
     inherit Attribute ()
 
+    /// The default value of `isExtensionMethod`, the optional argument to the ArgParserAttribute constructor.
+    static member DefaultIncludeFlagLike = false
+
+    /// Shorthand for the "includeFlagLike = false" constructor; see documentation there for details.
+    new () = PositionalArgsAttribute PositionalArgsAttribute.DefaultIncludeFlagLike
+
 /// Attribute indicating that this field shall have a default value derived
 /// from calling an appropriately named static method on the type.
 ///

WoofWare.Myriad.Plugins.Attributes/SurfaceBaseline.txt

@@ -40,7 +40,10 @@ WoofWare.Myriad.Plugins.JsonSerializeAttribute.get_DefaultIsExtensionMethod [sta
 WoofWare.Myriad.Plugins.ParseExactAttribute inherit System.Attribute
 WoofWare.Myriad.Plugins.ParseExactAttribute..ctor [constructor]: string
 WoofWare.Myriad.Plugins.PositionalArgsAttribute inherit System.Attribute
+WoofWare.Myriad.Plugins.PositionalArgsAttribute..ctor [constructor]: bool
 WoofWare.Myriad.Plugins.PositionalArgsAttribute..ctor [constructor]: unit
+WoofWare.Myriad.Plugins.PositionalArgsAttribute.DefaultIncludeFlagLike [static property]: [read-only] bool
+WoofWare.Myriad.Plugins.PositionalArgsAttribute.get_DefaultIncludeFlagLike [static method]: unit -> bool
 WoofWare.Myriad.Plugins.RemoveOptionsAttribute inherit System.Attribute
 WoofWare.Myriad.Plugins.RemoveOptionsAttribute..ctor [constructor]: unit
 WoofWare.Myriad.Plugins.RestEase inherit obj

WoofWare.Myriad.Plugins.Attributes/version.json

@@ -1,5 +1,5 @@
 {
-  "version": "3.4",
+  "version": "3.5",
   "publicReleaseRefSpec": [
     "^refs/heads/main$"
   ],

WoofWare.Myriad.Plugins.Test/TestArgParser/TestArgParser.fs

@@ -618,3 +618,89 @@ Required argument '--exact' received no value"""
             """Help text requested.
 --do-something-else / --anotherarg  string
 --turn-it-on / --dont-turn-it-off  bool"""
+
+    [<Test>]
+    let ``Can collect *all* non-help args into positional args with includeFlagLike`` () =
+        let getEnvVar (_ : string) = failwith "do not call"
+
+        FlagsIntoPositionalArgs.parse' getEnvVar [ "--a" ; "foo" ; "--b=false" ; "--c" ; "hi" ; "--" ; "--help" ]
+        |> shouldEqual
+            {
+                A = "foo"
+                GrabEverything = [ "--b=false" ; "--c" ; "hi" ; "--help" ]
+            }
+
+        // Users might consider this eccentric!
+        // But we're only a simple arg parser; we don't look around to see whether this is "almost"
+        // a valid parse.
+        FlagsIntoPositionalArgs.parse' getEnvVar [ "--a" ; "--b=false" ; "--c" ; "hi" ; "--" ; "--help" ]
+        |> shouldEqual
+            {
+                A = "--b=false"
+                GrabEverything = [ "--c" ; "hi" ; "--help" ]
+            }
+
+    [<Test>]
+    let ``Can collect non-help args into positional args with Choice`` () =
+        let getEnvVar (_ : string) = failwith "do not call"
+
+        FlagsIntoPositionalArgsChoice.parse' getEnvVar [ "--a" ; "foo" ; "--b=false" ; "--c" ; "hi" ; "--" ; "--help" ]
+        |> shouldEqual
+            {
+                A = "foo"
+                GrabEverything =
+                    [
+                        Choice1Of2 "--b=false"
+                        Choice1Of2 "--c"
+                        Choice1Of2 "hi"
+                        Choice2Of2 "--help"
+                    ]
+            }
+
+    [<Test>]
+    let ``Can collect non-help args into positional args, and we parse on the way`` () =
+        let getEnvVar (_ : string) = failwith "do not call"
+
+        FlagsIntoPositionalArgsInt.parse' getEnvVar [ "3" ; "--a" ; "foo" ; "5" ; "--" ; "98" ]
+        |> shouldEqual
+            {
+                A = "foo"
+                GrabEverything = [ 3 ; 5 ; 98 ]
+            }
+
+    [<Test>]
+    let ``Can collect non-help args into positional args with Choice, and we parse on the way`` () =
+        let getEnvVar (_ : string) = failwith "do not call"
+
+        FlagsIntoPositionalArgsIntChoice.parse' getEnvVar [ "3" ; "--a" ; "foo" ; "5" ; "--" ; "98" ]
+        |> shouldEqual
+            {
+                A = "foo"
+                GrabEverything = [ Choice1Of2 3 ; Choice1Of2 5 ; Choice2Of2 98 ]
+            }
+
+    [<Test>]
+    let ``Can refuse to collect non-help args with PositionalArgs false`` () =
+        let getEnvVar (_ : string) = failwith "do not call"
+
+        let exc =
+            Assert.Throws<exn> (fun () ->
+                FlagsIntoPositionalArgs'.parse'
+                    getEnvVar
+                    [ "--a" ; "foo" ; "--b=false" ; "--c" ; "hi" ; "--" ; "--help" ]
+                |> ignore<FlagsIntoPositionalArgs'>
+            )
+
+        exc.Message
+        |> shouldEqual """Unable to process argument --b=false as key --b and value false"""
+
+        let exc =
+            Assert.Throws<exn> (fun () ->
+                FlagsIntoPositionalArgs'.parse' getEnvVar [ "--a" ; "--b=false" ; "--c=hi" ; "--" ; "--help" ]
+                |> ignore<FlagsIntoPositionalArgs'>
+            )
+
+        // Again perhaps eccentric!
+        // Again, we don't try to detect that the user has missed out the desired argument to `--a`.
+        exc.Message
+        |> shouldEqual """Unable to process argument --c=hi as key --c and value hi"""

WoofWare.Myriad.Plugins/ArgParserGenerator.fs

@@ -85,8 +85,8 @@ type private ParseFunction<'acc> =
 
 [<RequireQualifiedAccess>]
 type private ChoicePositional =
-    | Normal
-    | Choice
+    | Normal of includeFlagLike : SynExpr option
+    | Choice of includeFlagLike : SynExpr option
 
 type private ParseFunctionPositional = ParseFunction<ChoicePositional>
 type private ParseFunctionNonPositional = ParseFunction<Accumulation<ArgumentDefaultSpec>>
@@ -506,11 +506,14 @@ module internal ArgParserGenerator =
 
                 let positionalArgAttr =
                     attrs
-                    |> List.tryFind (fun a ->
+                    |> List.tryPick (fun a ->
                         match (List.last a.TypeName.LongIdent).idText with
                         | "PositionalArgsAttribute"
-                        | "PositionalArgs" -> true
-                        | _ -> false
+                        | "PositionalArgs" ->
+                            match a.ArgExpr with
+                            | SynExpr.Const (SynConst.Unit, _) -> Some None
+                            | a -> Some (Some a)
+                        | _ -> None
                     )
 
                 let parseExactModifier =
@@ -580,7 +583,7 @@ module internal ArgParserGenerator =
                 | None ->
 
                 match positionalArgAttr with
-                | Some _ ->
+                | Some includeFlagLike ->
                     let getChoice (spec : ArgumentDefaultSpec option) : unit =
                         match spec with
                         | Some _ ->
@@ -607,7 +610,7 @@ module internal ArgParserGenerator =
                             FieldName = ident
                             Parser = parser
                             TargetVariable = Ident.create $"arg_%i{counter}"
-                            Accumulation = ChoicePositional.Choice
+                            Accumulation = ChoicePositional.Choice includeFlagLike
                             TargetType = parseTy
                             ArgForm = longForms
                             Help = helpText
@@ -619,7 +622,7 @@ module internal ArgParserGenerator =
                             FieldName = ident
                             Parser = parser
                             TargetVariable = Ident.create $"arg_%i{counter}"
-                            Accumulation = ChoicePositional.Normal
+                            Accumulation = ChoicePositional.Normal includeFlagLike
                             TargetType = parseTy
                             ArgForm = longForms
                             Help = helpText
@@ -855,8 +858,9 @@ module internal ArgParserGenerator =
                     |> SynExpr.pipeThroughFunction pos.Parser
                     |> fun p ->
                         match pos.Accumulation with
-                        | ChoicePositional.Choice -> p |> SynExpr.pipeThroughFunction (SynExpr.createIdent "Choice1Of2")
-                        | ChoicePositional.Normal -> p
+                        | ChoicePositional.Choice _ ->
+                            p |> SynExpr.pipeThroughFunction (SynExpr.createIdent "Choice1Of2")
+                        | ChoicePositional.Normal _ -> p
                     |> SynExpr.pipeThroughFunction (
                         SynExpr.createLongIdent' [ pos.TargetVariable ; Ident.create "Add" ]
                     )
@@ -1000,6 +1004,50 @@ module internal ArgParserGenerator =
             |> SynExpr.applyTo (SynExpr.createIdent "key")
             |> SynExpr.applyTo (SynExpr.createIdent "value")
 
+        let processAsPositional =
+            SynExpr.sequential
+                [
+                    SynExpr.createIdent "arg"
+                    |> SynExpr.pipeThroughFunction leftoverArgParser
+                    |> fun p ->
+                        match leftoverArgAcc with
+                        | ChoicePositional.Normal _ -> p
+                        | ChoicePositional.Choice _ ->
+                            p |> SynExpr.pipeThroughFunction (SynExpr.createIdent "Choice1Of2")
+                    |> SynExpr.pipeThroughFunction (SynExpr.createLongIdent' [ leftoverArgs ; Ident.create "Add" ])
+
+                    recurseKey
+                ]
+
+        let posAttr =
+            match leftoverArgAcc with
+            | ChoicePositional.Choice a
+            | ChoicePositional.Normal a -> a
+
+        let notMatched =
+            let handleFailure =
+                [
+                    SynMatchClause.create (SynPat.named "None") fail
+
+                    SynMatchClause.create
+                        (SynPat.nameWithArgs "Some" [ SynPat.named "msg" ])
+                        (SynExpr.sequential
+                            [
+                                SynExpr.createIdent "sprintf"
+                                |> SynExpr.applyTo (SynExpr.CreateConst "%s (at arg %s)")
+                                |> SynExpr.applyTo (SynExpr.createIdent "msg")
+                                |> SynExpr.applyTo (SynExpr.createIdent "arg")
+                                |> SynExpr.pipeThroughFunction (SynExpr.dotGet "Add" (SynExpr.createIdent' errorAcc))
+
+                                recurseKey
+                            ])
+                ]
+                |> SynExpr.createMatch (SynExpr.createIdent "x")
+
+            match posAttr with
+            | None -> handleFailure
+            | Some posAttr -> SynExpr.ifThenElse posAttr handleFailure processAsPositional
+
         let argStartsWithDashes =
             SynExpr.createIdent "arg"
             |> SynExpr.callMethodArg
@@ -1013,19 +1061,7 @@ module internal ArgParserGenerator =
         let processKey =
             SynExpr.ifThenElse
                 argStartsWithDashes
-                (SynExpr.sequential
-                    [
-                        SynExpr.createIdent "arg"
-                        |> SynExpr.pipeThroughFunction leftoverArgParser
-                        |> fun p ->
-                            match leftoverArgAcc with
-                            | ChoicePositional.Normal -> p
-                            | ChoicePositional.Choice ->
-                                p |> SynExpr.pipeThroughFunction (SynExpr.createIdent "Choice1Of2")
-                        |> SynExpr.pipeThroughFunction (SynExpr.createLongIdent' [ leftoverArgs ; Ident.create "Add" ])
-
-                        recurseKey
-                    ])
+                processAsPositional
                 (SynExpr.ifThenElse
                     (SynExpr.equals (SynExpr.createIdent "arg") (SynExpr.CreateConst "--help"))
                     (SynExpr.createLet
@@ -1061,23 +1097,9 @@ module internal ArgParserGenerator =
                                     [
                                         SynMatchClause.create (SynPat.nameWithArgs "Ok" [ SynPat.unit ]) recurseKey
 
-                                        SynMatchClause.create (SynPat.nameWithArgs "Error" [ SynPat.named "None" ]) fail
                                         SynMatchClause.create
-                                            (SynPat.nameWithArgs
-                                                "Error"
-                                                [ SynPat.nameWithArgs "Some" [ SynPat.named "msg" ] |> SynPat.paren ])
-                                            (SynExpr.sequential
-                                                [
-                                                    SynExpr.createIdent "sprintf"
-                                                    |> SynExpr.applyTo (SynExpr.CreateConst "%s (at arg %s)")
-                                                    |> SynExpr.applyTo (SynExpr.createIdent "msg")
-                                                    |> SynExpr.applyTo (SynExpr.createIdent "arg")
-                                                    |> SynExpr.pipeThroughFunction (
-                                                        SynExpr.dotGet "Add" (SynExpr.createIdent' errorAcc)
-                                                    )
-
-                                                    recurseKey
-                                                ])
+                                            (SynPat.nameWithArgs "Error" [ SynPat.named "x" ])
+                                            notMatched
                                     ]))
                             (SynExpr.createIdent "args" |> SynExpr.pipeThroughFunction recurseValue)))
                     (SynExpr.createIdent "helpText"
@@ -1091,6 +1113,8 @@ module internal ArgParserGenerator =
         let processValue =
             // During failure, we've received an optional exception message that happened when we tried to parse
             // the value; it's in the variable `exc`.
+            // `fail` is for the case where we're genuinely emitting an error.
+            // If we're in `PositionalArgs true` mode, though, we won't call `fail`.
             let fail =
                 [
                     SynExpr.createIdent "failwithf"
@@ -1110,6 +1134,27 @@ module internal ArgParserGenerator =
                 ]
                 |> SynExpr.createMatch (SynExpr.createIdent "exc")
 
+            let onFailure =
+                match posAttr with
+                | None -> fail
+                | Some includeFlagLike ->
+                    [
+                        SynExpr.createIdent "key"
+                        |> SynExpr.pipeThroughFunction leftoverArgParser
+                        |> fun i ->
+                            match leftoverArgAcc with
+                            | ChoicePositional.Choice _ ->
+                                i |> SynExpr.pipeThroughFunction (SynExpr.createIdent "Choice1Of2")
+                            | ChoicePositional.Normal _ -> i
+                        |> SynExpr.pipeThroughFunction (SynExpr.createLongIdent' [ leftoverArgs ; Ident.create "Add" ])
+
+                        SynExpr.createIdent "go"
+                        |> SynExpr.applyTo (SynExpr.createLongIdent' [ parseState ; Ident.create "AwaitingKey" ])
+                        |> SynExpr.applyTo (SynExpr.listCons (SynExpr.createIdent "arg") (SynExpr.createIdent "args"))
+                    ]
+                    |> SynExpr.sequential
+                    |> SynExpr.ifThenElse includeFlagLike fail
+
             [
                 SynMatchClause.create
                     (SynPat.nameWithArgs "Ok" [ SynPat.unit ])
@@ -1122,7 +1167,7 @@ module internal ArgParserGenerator =
                     (SynPat.nameWithArgs "Error" [ SynPat.named "exc" ])
                     (SynExpr.ifThenElse
                         (SynExpr.applyFunction (SynExpr.createIdent "setFlagValue") (SynExpr.createIdent "key"))
-                        fail
+                        onFailure
                         (SynExpr.createIdent "go"
                          |> SynExpr.applyTo (SynExpr.createLongIdent' [ parseState ; Ident.create "AwaitingKey" ])
                          |> SynExpr.applyTo (SynExpr.listCons (SynExpr.createIdent "arg") (SynExpr.createIdent "args"))))
@@ -1189,8 +1234,8 @@ module internal ArgParserGenerator =
                             )
                             |> fun p ->
                                 match leftoverArgAcc with
-                                | ChoicePositional.Normal -> p
-                                | ChoicePositional.Choice ->
+                                | ChoicePositional.Normal _ -> p
+                                | ChoicePositional.Choice _ ->
                                     p
                                     |> SynExpr.pipeThroughFunction (
                                         SynExpr.applyFunction
@@ -1262,9 +1307,9 @@ module internal ArgParserGenerator =
                     SynType.string
                 | Some pf ->
                     match pf.Accumulation with
-                    | ChoicePositional.Choice ->
+                    | ChoicePositional.Choice _ ->
                         pf.TargetVariable, pf.Parser, SynType.app "Choice" [ pf.TargetType ; pf.TargetType ]
-                    | ChoicePositional.Normal -> pf.TargetVariable, pf.Parser, pf.TargetType
+                    | ChoicePositional.Normal _ -> pf.TargetVariable, pf.Parser, pf.TargetType
 
             let bindings =
                 SynExpr.createIdent "ResizeArray"
@@ -1492,7 +1537,7 @@ module internal ArgParserGenerator =
 
         let leftoverArgAcc =
             match pos with
-            | None -> ChoicePositional.Normal
+            | None -> ChoicePositional.Normal None
             | Some pos -> pos.Accumulation
 
         [

WoofWare.Myriad.Plugins/CataGenerator.fs

@@ -564,11 +564,12 @@ module internal CataGenerator =
                     let domain =
                         field.FieldName
                         |> Option.map Ident.lowerFirstLetter
-                        |> SynType.signatureParamOfType place
+                        |> SynType.signatureParamOfType [] place false
 
                     acc |> SynType.funFromDomain domain
                 )
                 |> SynMemberDefn.abstractMember
+                    []
                     case.CataMethodIdent
                     None
                     arity

WoofWare.Myriad.Plugins/InterfaceMockGenerator.fs

@@ -228,14 +228,11 @@ module internal InterfaceMockGenerator =
             x.Type
 
     let private constructMemberSinglePlace (tuple : TupledArg) : SynType =
-        match tuple.Args |> List.rev |> List.map buildType with
-        | [] -> failwith "no-arg functions not supported yet"
-        | [ x ] -> x
-        | last :: rest ->
-            ([ SynTupleTypeSegment.Type last ], rest)
-            ||> List.fold (fun ty nextArg -> SynTupleTypeSegment.Type nextArg :: SynTupleTypeSegment.Star range0 :: ty)
-            |> fun segs -> SynType.Tuple (false, segs, range0)
-        |> fun ty -> if tuple.HasParen then SynType.Paren (ty, range0) else ty
+        tuple.Args
+        |> List.map buildType
+        |> SynType.tupleNoParen
+        |> Option.defaultWith (fun () -> failwith "no-arg functions not supported yet")
+        |> if tuple.HasParen then SynType.paren else id
 
     let constructMember (mem : MemberInfo) : SynField =
         let inputType = mem.Args |> List.map constructMemberSinglePlace

WoofWare.Myriad.Plugins/SynExpr/Ident.fs

@@ -2,6 +2,7 @@ namespace WoofWare.Myriad.Plugins
 
 open System
 open System.Text
+open System.Text.RegularExpressions
 open Fantomas.FCS.Syntax
 open Fantomas.FCS.Text.Range
 
@@ -9,6 +10,53 @@ open Fantomas.FCS.Text.Range
 module internal Ident =
     let inline create (s : string) = Ident (s, range0)
 
+    /// Fantomas bug, perhaps? "type" is not rendered as ``type``, although the ASTs are identical
+    /// apart from the ranges?
+    /// Awful hack: here is a function that does this sort of thing.
+    let createSanitisedParamName (s : string) =
+        match s with
+        | "type" -> create "type'"
+        | _ ->
+
+        let result = StringBuilder ()
+
+        for i = 0 to s.Length - 1 do
+            if Char.IsLetter s.[i] then
+                result.Append s.[i] |> ignore<StringBuilder>
+            elif Char.IsNumber s.[i] then
+                if result.Length > 0 then
+                    result.Append s.[i] |> ignore<StringBuilder>
+            elif s.[i] = '_' || s.[i] = '-' then
+                result.Append '_' |> ignore<StringBuilder>
+            else
+                failwith $"could not convert to ident: %s{s}"
+
+        create (result.ToString ())
+
+    let private alnum = Regex @"^[a-zA-Z][a-zA-Z0-9]*$"
+
+    let createSanitisedTypeName (s : string) =
+        let result = StringBuilder ()
+        let mutable capitalize = true
+
+        for i = 0 to s.Length - 1 do
+            if Char.IsLetter s.[i] then
+                if capitalize then
+                    result.Append (Char.ToUpperInvariant s.[i]) |> ignore<StringBuilder>
+                    capitalize <- false
+                else
+                    result.Append s.[i] |> ignore<StringBuilder>
+            elif Char.IsNumber s.[i] then
+                if result.Length > 0 then
+                    result.Append s.[i] |> ignore<StringBuilder>
+            elif s.[i] = '_' then
+                capitalize <- true
+
+        if result.Length = 0 then
+            failwith $"String %s{s} was not suitable as a type identifier"
+
+        Ident (result.ToString (), range0)
+
     let lowerFirstLetter (x : Ident) : Ident =
         let result = StringBuilder x.idText.Length
         result.Append (Char.ToLowerInvariant x.idText.[0]) |> ignore

WoofWare.Myriad.Plugins/SynExpr/PreXmlDoc.fs

@@ -6,7 +6,12 @@ open Fantomas.FCS.Text.Range
 [<RequireQualifiedAccess>]
 module internal PreXmlDoc =
     let create (s : string) : PreXmlDoc =
-        PreXmlDoc.Create ([| " " + s |], range0)
+        let s = s.Split "\n"
+
+        for i = 0 to s.Length - 1 do
+            s.[i] <- " " + s.[i]
+
+        PreXmlDoc.Create (s, range0)
 
     let create' (s : string seq) : PreXmlDoc =
         PreXmlDoc.Create (Array.ofSeq s, range0)

WoofWare.Myriad.Plugins/SynExpr/SynArgPats.fs

@@ -9,12 +9,12 @@ module internal SynArgPats =
         match caseNames.Length with
         | 0 -> SynArgPats.Pats []
         | 1 ->
-            SynPat.Named (SynIdent.SynIdent (Ident.create caseNames.[0], None), false, None, range0)
+            SynPat.Named (SynIdent.createS caseNames.[0], false, None, range0)
             |> List.singleton
             |> SynArgPats.Pats
         | len ->
             caseNames
-            |> List.map (fun name -> SynPat.Named (SynIdent.SynIdent (Ident.create name, None), false, None, range0))
+            |> List.map (fun name -> SynPat.Named (SynIdent.createS name, false, None, range0))
             |> fun t -> SynPat.Tuple (false, t, List.replicate (len - 1) range0, range0)
             |> fun t -> SynPat.Paren (t, range0)
             |> List.singleton

WoofWare.Myriad.Plugins/SynExpr/SynAttribute.fs

@@ -5,32 +5,23 @@ open Fantomas.FCS.Text.Range
 
 [<RequireQualifiedAccess>]
 module internal SynAttribute =
-    let internal compilationRepresentation : SynAttribute =
+    let inline create (typeName : SynLongIdent) (arg : SynExpr) : SynAttribute =
         {
-            TypeName = SynLongIdent.createS "CompilationRepresentation"
-            ArgExpr =
-                [ "CompilationRepresentationFlags" ; "ModuleSuffix" ]
-                |> SynExpr.createLongIdent
-                |> SynExpr.paren
+            TypeName = typeName
+            ArgExpr = arg
             Target = None
             AppliesToGetterAndSetter = false
             Range = range0
         }
 
+    let internal compilationRepresentation : SynAttribute =
+        [ "CompilationRepresentationFlags" ; "ModuleSuffix" ]
+        |> SynExpr.createLongIdent
+        |> SynExpr.paren
+        |> create (SynLongIdent.createS "CompilationRepresentation")
+
     let internal requireQualifiedAccess : SynAttribute =
-        {
-            TypeName = SynLongIdent.createS "RequireQualifiedAccess"
-            ArgExpr = SynExpr.CreateConst ()
-            Target = None
-            AppliesToGetterAndSetter = false
-            Range = range0
-        }
+        create (SynLongIdent.createS "RequireQualifiedAccess") (SynExpr.CreateConst ())
 
     let internal autoOpen : SynAttribute =
-        {
-            TypeName = SynLongIdent.createS "AutoOpen"
-            ArgExpr = SynExpr.CreateConst ()
-            Target = None
-            AppliesToGetterAndSetter = false
-            Range = range0
-        }
+        create (SynLongIdent.createS "AutoOpen") (SynExpr.CreateConst ())

WoofWare.Myriad.Plugins/SynExpr/SynExpr.fs

@@ -80,6 +80,11 @@ module internal SynExpr =
     let equals (a : SynExpr) (b : SynExpr) =
         SynExpr.CreateAppInfix (SynExpr.CreateLongIdent SynLongIdent.eq, a) |> applyTo b
 
+    /// {a} && {b}
+    let booleanAnd (a : SynExpr) (b : SynExpr) =
+        SynExpr.CreateAppInfix (SynExpr.CreateLongIdent SynLongIdent.booleanAnd, a)
+        |> applyTo b
+
     /// {a} + {b}
     let plus (a : SynExpr) (b : SynExpr) =
         SynExpr.CreateAppInfix (

WoofWare.Myriad.Plugins/SynExpr/SynIdent.fs

@@ -0,0 +1,10 @@
+namespace WoofWare.Myriad.Plugins
+
+open Fantomas.FCS.Syntax
+
+[<RequireQualifiedAccess>]
+module internal SynIdent =
+    let inline createI (i : Ident) : SynIdent = SynIdent.SynIdent (i, None)
+
+    let inline createS (i : string) : SynIdent =
+        SynIdent.SynIdent (Ident.create i, None)

WoofWare.Myriad.Plugins/SynExpr/SynLongIdent.fs

@@ -33,6 +33,9 @@ module internal SynLongIdent =
     let eq =
         SynLongIdent.SynLongIdent ([ Ident.create "op_Equality" ], [], [ Some (IdentTrivia.OriginalNotation "=") ])
 
+    let booleanAnd =
+        SynLongIdent.SynLongIdent ([ Ident.create "op_BooleanAnd" ], [], [ Some (IdentTrivia.OriginalNotation "&&") ])
+
     let pipe =
         SynLongIdent.SynLongIdent ([ Ident.create "op_PipeRight" ], [], [ Some (IdentTrivia.OriginalNotation "|>") ])
 

WoofWare.Myriad.Plugins/SynExpr/SynMemberDefn.fs

@@ -17,8 +17,8 @@ module internal SynMemberDefn =
             SynMemberFlags.MemberKind = SynMemberKind.Member
         }
 
-
     let abstractMember
+        (attrs : SynAttribute list)
         (ident : SynIdent)
         (typars : SynTyparDecls option)
         (arity : SynValInfo)
@@ -28,7 +28,13 @@ module internal SynMemberDefn =
         =
         let slot =
             SynValSig.SynValSig (
-                [],
+                attrs
+                |> List.map (fun attr ->
+                    {
+                        Attributes = [ attr ]
+                        Range = range0
+                    }
+                ),
                 ident,
                 SynValTyparDecls.SynValTyparDecls (typars, true),
                 returnType,

WoofWare.Myriad.Plugins/SynExpr/SynType.fs

@@ -267,6 +267,8 @@ module internal SynType =
         | SynType.Paren (ty, _) -> stripOptionalParen ty
         | ty -> ty
 
+    let inline paren (ty : SynType) : SynType = SynType.Paren (ty, range0)
+
     let inline createLongIdent (ident : LongIdent) : SynType =
         SynType.LongIdent (SynLongIdent.create ident)
 
@@ -283,6 +285,17 @@ module internal SynType =
 
     let inline app (name : string) (args : SynType list) : SynType = app' (named name) args
 
+    /// Returns None if the input list was empty.
+    let inline tupleNoParen (ty : SynType list) : SynType option =
+        match List.rev ty with
+        | [] -> None
+        | [ t ] -> Some t
+        | t :: rest ->
+            ([ SynTupleTypeSegment.Type t ], rest)
+            ||> List.fold (fun ty nextArg -> SynTupleTypeSegment.Type nextArg :: SynTupleTypeSegment.Star range0 :: ty)
+            |> fun segs -> SynType.Tuple (false, segs, range0)
+            |> Some
+
     let inline appPostfix (name : string) (arg : SynType) : SynType =
         SynType.App (named name, None, [ arg ], [], None, true, range0)
 
@@ -299,16 +312,54 @@ module internal SynType =
             }
         )
 
-    let inline signatureParamOfType (ty : SynType) (name : Ident option) : SynType =
-        SynType.SignatureParameter ([], false, name, ty, range0)
+    let inline signatureParamOfType
+        (attrs : SynAttribute list)
+        (ty : SynType)
+        (optional : bool)
+        (name : Ident option)
+        : SynType
+        =
+        SynType.SignatureParameter (
+            attrs
+            |> List.map (fun attr ->
+                {
+                    Attributes = [ attr ]
+                    Range = range0
+                }
+            ),
+            optional,
+            name,
+            ty,
+            range0
+        )
 
     let inline var (ty : SynTypar) : SynType = SynType.Var (ty, range0)
 
     let unit : SynType = named "unit"
+    let obj : SynType = named "obj"
+    let bool : SynType = named "bool"
     let int : SynType = named "int"
+    let array (elt : SynType) : SynType = SynType.Array (1, elt, range0)
+
+    let list (elt : SynType) : SynType =
+        SynType.App (named "list", None, [ elt ], [], None, true, range0)
+
+    let option (elt : SynType) : SynType =
+        SynType.App (named "option", None, [ elt ], [], None, true, range0)
 
     let anon : SynType = SynType.Anon range0
 
+    let task (elt : SynType) : SynType =
+        SynType.App (
+            createLongIdent' [ "System" ; "Threading" ; "Tasks" ; "Task" ],
+            None,
+            [ elt ],
+            [],
+            None,
+            true,
+            range0
+        )
+
     let string : SynType = named "string"
 
     /// Given ['a1, 'a2] and 'ret, returns 'a1 -> 'a2 -> 'ret.

WoofWare.Myriad.Plugins/SynExpr/SynUnionCase.fs

@@ -44,7 +44,7 @@ module internal SynUnionCase =
 
         SynUnionCase.SynUnionCase (
             SynAttributes.ofAttrs case.Attributes,
-            SynIdent.SynIdent (case.Name, None),
+            SynIdent.createI case.Name,
             SynUnionCaseKind.Fields fields,
             case.XmlDoc |> Option.defaultValue PreXmlDoc.Empty,
             case.Access,

WoofWare.Myriad.Plugins/WoofWare.Myriad.Plugins.fsproj

@@ -30,6 +30,7 @@
     <Compile Include="SynExpr\SynAttributes.fs" />
     <Compile Include="SynExpr\PreXmlDoc.fs" />
     <Compile Include="SynExpr\Ident.fs" />
+    <Compile Include="SynExpr\SynIdent.fs" />
     <Compile Include="SynExpr\SynLongIdent.fs" />
     <Compile Include="SynExpr\SynExprLetOrUseTrivia.fs" />
     <Compile Include="SynExpr\SynArgPats.fs" />