Normalization by Evaluation

Optimizing F# quotations by applying Normalization-by-Evaluation

Implementation

open System
open System.Reflection
open FSharp.Reflection
open FSharp.Quotations
open FSharp.Quotations.Patterns
open FSharp.Quotations.DerivedPatterns
open FSharp.Quotations.ExprShape

// Semantic interpretation of quotation trees
type Sem =
    | VAR of Var * value:Sem option
    | LIT of obj * Type
    | LAM of Var * Sem * (Sem -> Sem)
    | LET of Var * Sem * Sem
    | TUPLE of Type * Sem list
    | RECORD of Type * Sem list
    | UNION of UnionCaseInfo * Sem list
    | UPCAST of Sem * Type
    // Standard arithmetic operator expression
    | OP of MethodInfo * Sem list
    // Embeds arbitrary syntactic trees
    | SYN of expr:Expr * isPureNode:bool * shape:obj * args:Sem list

/// determines if expression is guaranteed to evaluate without side-effects
let rec isPure (s : Sem) =
    match s with
    | VAR (v,_) -> not v.IsMutable
    | LIT _ | LAM _ -> true
    | LET(_,b,k) -> isPure b && isPure k
    | UPCAST (s,_) -> isPure s
    | TUPLE (_,fs) | RECORD (_,fs) | UNION(_,fs) | OP(_,fs) -> fs |> List.forall isPure
    | SYN(isPureNode = isPureNode; args = args) -> isPureNode && args |> List.forall isPure

let rec getType reflect (s : Sem) =
    match s with
    | VAR (v, None) -> v.Type
    | VAR (_, Some s) -> getType reflect s
    | LIT (null, t) -> t
    | LIT (o, _) -> o.GetType()
    | LAM (v, s, _) -> FSharpType.MakeFunctionType(v.Type, getType false s)
    | LET (_,_,k) -> getType reflect k
    | UPCAST (s,t) -> if reflect then getType reflect s else t
    | TUPLE (t,_) -> t
    | RECORD (t,_) -> t
    | UNION(uci,_) -> uci.DeclaringType
    | OP(mi,_) -> mi.ReturnType
    | SYN(expr = e) -> e.Type

/// determines if the two types are in a subtype relationship
let rec isSubtypeOf (iface : Type) (ty : Type) =
    let proj (t : Type) = t.Assembly, t.Namespace, t.Name, t.MetadataToken
    if iface.IsAssignableFrom ty then true
    elif ty.GetInterfaces() |> Array.exists(fun if0 -> proj if0 = proj iface) then true
    else
        match ty.BaseType with
        | null -> false
        | bt -> isSubtypeOf iface bt

let rec containsReference (v : Var) (s : Sem) =
    match s with
    | VAR (w, _) -> v = w
    | LIT _ -> false
    | LAM (_, b, _) -> containsReference v b
    | LET (_, b, k) -> containsReference v b || containsReference v k
    | UPCAST (s, _) -> containsReference v s
    | TUPLE (_, args)
    | RECORD (_, args)
    | UNION (_, args)
    | OP (_, args)
    | SYN (_, _, _, args) -> args |> List.exists (containsReference v)

type Environment = Map<Var, Sem>

/// Maps syntactic trees to semantic expressions; apply optimizations as required
let rec meaning (env : Environment) (expr : Expr) : Sem =
    let mkLit (x : 'T) = LIT(x, typeof<'T>)

    let (|Deref|) s =
        match s with
        | VAR(_, Some s) -> s
        | _ -> s

    let mkLet v sbind skont =
        // if binding is pure and variable not referenced in kont, eliminate the let
        if isPure sbind && skont |> containsReference v |> not then skont
        else LET(v, sbind, skont)

    // fallback mapping: use trivial expression node embedding
    let fallback (env : Environment) (expr : Expr) =
        match expr with
        | ShapeCombination(shape, args) ->
            let sargs = args |> List.map (meaning env)
            let isPureNode =
                match expr with
                | IfThenElse _
                | TupleGet _
                | TypeTest _
                | UnionCaseTest _
                | LetRecursive _
                | QuoteRaw _
                | QuoteTyped _ -> true
                | PropertyGet(Some e, _, []) when 
                    FSharpType.IsRecord(e.Type, true) || 
                    FSharpType.IsUnion(e.Type, true) ||
                    FSharpType.IsTuple(e.Type) -> true
                | _ -> false

            SYN(expr, isPureNode, shape, sargs)

        | ShapeVar _ | ShapeLambda _ -> failwith "internal error"
        
    match expr with
    | Value(o, t) -> LIT(o, t)
    | Var v -> 
        match env.TryFind v with
        | Some (LIT _ | VAR _ as s) -> s
        | sopt -> VAR(v, sopt)

    | Lambda(v, body) -> 
        let slam s = meaning (env.Add(v, s)) body
        LAM(v, slam (VAR(v, None)), slam)

    | Application(f, g) ->
        match meaning env f with
        | Deref (LAM (v, _, lam)) ->
            match meaning env g with
            // (λ x. M) N ~> M[N/x]
            | LIT _ | VAR _ | LAM _ as s -> lam s
            // (λ x. M) N ~> let x = N in M
            | sbind -> mkLet v sbind (lam (VAR(v, Some sbind)))

        | _ -> fallback env expr

    | Let(v, bind, kont) when not v.IsMutable ->
        let sbind = meaning env bind
        match meaning (env.Add(v, sbind)) kont with
        // let x = N in x ~> N
        | VAR(x, _) when x = v -> sbind 
        // let x = expr in M ~> M
        | skont -> mkLet v sbind skont

    | IfThenElse(cond, ifExpr, elseExpr) ->
        match meaning env cond with
        | Deref (LIT(:? bool as ccond, _)) ->
            // branch elimination
            let branch = if ccond then ifExpr else elseExpr
            meaning env branch
        | _ -> fallback env expr

    | Sequential(left, right) ->
        match meaning env left with
        | ls when isPure ls -> meaning env right
        | _ -> fallback env expr

    // Tuple introduction & elimination [https://github.com/dotnet/fsharp/issues/7914]
    | NewTuple ts when not expr.Type.IsValueType -> TUPLE(expr.Type, ts |> List.map (meaning env))
    | TupleGet(tuple, i) ->
        match meaning env tuple with
        | Deref (TUPLE (_, ts)) -> ts.[i]
        | _ -> fallback env expr

    // Record introduction & elimination
    | NewRecord(t, fs) -> RECORD(t, fs |> List.map (meaning env))
    | PropertyGet(Some e, prop, []) ->
        match meaning env e with
        | Deref (RECORD(t,fs)) -> 
            match FSharpType.GetRecordFields(t, true) |> Array.tryFindIndex(fun p -> prop = p) with
            | Some i -> fs.[i]
            | None -> fallback env expr
        | Deref (UNION(uci, fs)) ->
            match uci.GetFields() |> Array.tryFindIndex(fun p -> prop = p) with
            | Some i -> fs.[i]
            | None -> fallback env expr
        | _ -> fallback env expr

    // Union introduction & elimination
    | NewUnionCase(uci, fs) -> UNION(uci, fs |> List.map (meaning env))
    | UnionCaseTest(e, uci) ->
        match meaning env e with
        | Deref (UNION(uci', _)) -> mkLit(uci = uci')
        | _ -> fallback env expr

    | TypeTest(e, t) ->
        let s = meaning env e
        let st = getType true s
        let staticTypeTestResult =
            if isSubtypeOf t st then Some true
            elif isSubtypeOf st t then None
            else Some false

        match staticTypeTestResult with
        | Some r -> meaning env (Expr.Sequential(e, Expr.Value r))
        | None -> fallback env expr

    | Coerce(e, t) ->
        let (s | UPCAST(s,_)) = meaning env e
        let st = getType true s
        if t = st then
            // UPCAST elimination: remove if expression type matches the reflected type
            let rec tryDeref s =
                match s with
                | LIT _ -> Some s
                | UPCAST(s, _) -> tryDeref s
                | VAR(_, Some v) ->
                    match tryDeref v with
                    | Some _ as r -> r
                    | None -> Some s

                // do not deref if expr is method
                // or other side-effectful operation
                | _ -> None

            match tryDeref s with
            | Some s when getType false s = t -> s
            | _ -> UPCAST(s, t)

        elif isSubtypeOf t st then UPCAST(s, t)
        else fallback env expr

    | SpecificCall <@ (=) @> (None, _, ([value; Value(null,_)] | [Value(null,_) ; value]))
    | SpecificCall <@ isNull @> (None, _, ([value])) ->
        match meaning env value with
        | Deref (LIT (x,_)) -> mkLit(obj.ReferenceEquals(x, null))
        | _ -> fallback env expr

    | SpecificCall <@ (<>) @> (None, _, ([value; Value(null,_)] | [Value(null,_) ; value])) ->
        match meaning env value with
        | Deref (LIT (x,_)) -> mkLit(not <| obj.ReferenceEquals(x, null))
        | _ -> fallback env expr

    | SpecificCall <@ (|>) @> (None, _, [value; func])
    | SpecificCall <@ (<|) @> (None, _, [func; value]) -> meaning env (Expr.Application(func, value))

    | SpecificCall <@ fst @> (None, _, [t]) -> meaning env (Expr.TupleGet(t, 0))
    | SpecificCall <@ snd @> (None, _, [t]) -> meaning env (Expr.TupleGet(t, 1))
    | SpecificCall <@ ignore @> (None, _, [value]) -> meaning env (Expr.Sequential(value, Expr.Value(())))

    | SpecificCall <@ box @> (None, _, [value])
    | SpecificCall <@ LanguagePrimitives.IntrinsicFunctions.UnboxGeneric @> (None, _, [value])
    | SpecificCall <@ LanguagePrimitives.IntrinsicFunctions.UnboxFast @> (None, _, [value])
    | SpecificCall <@ unbox @> (None, _, [value]) -> meaning env (Expr.Coerce(value, expr.Type))

    | Call(None, mi, args) when mi.DeclaringType.FullName = "Microsoft.FSharp.Core.Operators" && mi.Name.StartsWith "op_" ->
        let sargs = args |> List.map (meaning env)
        let literals = sargs |> Seq.choose (function (Deref (LIT(o,_))) -> Some o | _ -> None) |> Seq.toArray
        if literals.Length = sargs.Length then
            // evaluate constant expressions
            try LIT(mi.Invoke(null, literals), expr.Type)
            with :? TargetInvocationException as e when (e.InnerException :? NotSupportedException) ->
                // "Dynamic invocation of operator is not supported"
                OP(mi, sargs)
        else
            OP(mi, sargs)

    | _ -> fallback env expr

/// Maps semantic expressions back to a syntactic representation
let rec reify (s : Sem) : Expr =
    match s with
    | VAR (v, _) -> Expr.Var v
    | LIT (o, t) -> Expr.Value(o, t)
    | LAM (v, b, _) -> Expr.Lambda(v, reify b)
    | LET (v, b, k) -> Expr.Let(v, reify b, reify k)
    | UPCAST (s, t) -> Expr.Coerce(reify s, t)
    | TUPLE (_, fs) -> Expr.NewTuple(fs |> List.map reify)
    | RECORD (t, fs) -> Expr.NewRecord(t, fs |> List.map reify)
    | UNION (uci, fs) -> Expr.NewUnionCase(uci, fs |> List.map reify)
    | OP(mI, args) -> Expr.Call(mI, args |> List.map reify)
    | SYN(_, _, shape, sparams) -> RebuildShapeCombination(shape, sparams |> List.map reify)

/// Apply normalization-by-evaluation to quotation tree
let nbe (e : Expr<'a>) : Expr<'a> = e |> meaning Map.empty |> reify |> Expr.Cast

Examples

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let nbe_decompile expr = expr |> nbe |> Swensen.Unquote.Operators.decompile

nbe_decompile 
    <@
        let f x =
            match x with
            | Some i -> i > 0
            | None -> false

        f (Some 42), f None
    @>
// (true, false)

nbe_decompile 
    <@ 
        fun () -> 
            let mutable y = 0
            let f x = x + 2
            y <- f 2
            y + 1
    @>
// fun () -> let mutable y = 0 in y <- 4; y + 1

nbe_decompile 
    <@
        fun z ->
            let f x =
                if x > 0 then Console.WriteLine "Positive"
                elif x = 0 then Console.WriteLine "Zero"
                else Console.WriteLine "Negative"

            f -1; f 0; f z
    @>
// fun z -> 
//      Console.WriteLine("Negative")
//      Console.WriteLine("Zero")
//      if z > 0 then Console.WriteLine("Positive") 
//      else (if z = 0 then Console.WriteLine("Zero")
//      else Console.WriteLine("Negative"))

Stream pipelines

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// Nessos streams: http://trelford.com/blog/post/SeqVsStream.aspx
type Stream<'T> = ('T -> unit) -> unit

nbe_decompile
    <@
        let ofArray (xs : int []) =
            fun k -> for x in xs do k x

        let map : (int -> int) -> Stream<int> -> Stream<int> =
            fun f ts k -> ts (fun t -> k (f t))

        let filter : (int -> bool) -> Stream<int> -> Stream<int> =
            fun f ts k -> ts (fun t -> if (f t) then k t)

        let iter : (int -> unit) -> Stream<int> -> unit =
            fun f ts -> ts f

        fun xs ->
            ofArray xs
            |> filter (fun i -> i > 0)
            |> filter (fun i -> i % 2 = 0)
            |> map (fun i -> i * i)
            |> map (fun i -> i + i)
            |> iter (fun i -> printfn "%d" i)
    @>

//fun (xs : int []) ->
//    for x in xs do
//        if x > 0 then
//            if x % 2 = 0 then
//                let t = x * x
//                let i = t + t
//                printfn "%d" i

namespace System

namespace System.Reflection

namespace Microsoft.FSharp

namespace Microsoft.FSharp.Reflection

namespace Microsoft.FSharp.Quotations

module Patterns

from Microsoft.FSharp.Quotations

module DerivedPatterns

from Microsoft.FSharp.Quotations

module ExprShape

from Microsoft.FSharp.Quotations

union case Sem.VAR: Var * value: Sem option -> Sem

Multiple items
active recognizer Var: Expr -> Var option

Full name: Microsoft.FSharp.Quotations.Patterns.( |Var|_| )

--------------------
type Var =
  interface IComparable
  new : name:string * typ:Type * ?isMutable:bool -> Var
  member IsMutable : bool
  member Name : string
  member Type : Type
  static member Global : name:string * typ:Type -> Var

Full name: Microsoft.FSharp.Quotations.Var

--------------------
new : name:string * typ:Type * ?isMutable:bool -> Var

type 'T option = Option<'T>

Full name: Microsoft.FSharp.Core.option<_>

union case Sem.LIT: obj * Type -> Sem

type obj = Object

Full name: Microsoft.FSharp.Core.obj

type Type =
  inherit MemberInfo
  member Assembly : Assembly
  member AssemblyQualifiedName : string
  member Attributes : TypeAttributes
  member BaseType : Type
  member ContainsGenericParameters : bool
  member DeclaringMethod : MethodBase
  member DeclaringType : Type
  member Equals : o:obj -> bool + 1 overload
  member FindInterfaces : filter:TypeFilter * filterCriteria:obj -> Type[]
  member FindMembers : memberType:MemberTypes * bindingAttr:BindingFlags * filter:MemberFilter * filterCriteria:obj -> MemberInfo[]
  ...

Full name: System.Type

union case Sem.LAM: Var * Sem * (Sem -> Sem) -> Sem

union case Sem.LET: Var * Sem * Sem -> Sem

union case Sem.TUPLE: Type * Sem list -> Sem

type 'T list = List<'T>

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

union case Sem.RECORD: Type * Sem list -> Sem

union case Sem.UNION: UnionCaseInfo * Sem list -> Sem

type UnionCaseInfo
member GetCustomAttributes : unit -> obj []
member GetCustomAttributes : attributeType:Type -> obj []
member GetCustomAttributesData : unit -> IList<CustomAttributeData>
member GetFields : unit -> PropertyInfo []
member DeclaringType : Type
member Name : string
member Tag : int

Full name: Microsoft.FSharp.Reflection.UnionCaseInfo

union case Sem.UPCAST: Sem * Type -> Sem

union case Sem.OP: MethodInfo * Sem list -> Sem

type MethodInfo =
  inherit MethodBase
  member Equals : obj:obj -> bool
  member GetBaseDefinition : unit -> MethodInfo
  member GetGenericArguments : unit -> Type[]
  member GetGenericMethodDefinition : unit -> MethodInfo
  member GetHashCode : unit -> int
  member MakeGenericMethod : [<ParamArray>] typeArguments:Type[] -> MethodInfo
  member MemberType : MemberTypes
  member ReturnParameter : ParameterInfo
  member ReturnType : Type
  member ReturnTypeCustomAttributes : ICustomAttributeProvider

Full name: System.Reflection.MethodInfo

union case Sem.SYN: expr: Expr * isPureNode: bool * shape: obj * args: Sem list -> Sem

Multiple items
type Expr =
  override Equals : obj:obj -> bool
  member GetFreeVars : unit -> seq<Var>
  member Substitute : substitution:(Var -> Expr option) -> Expr
  member ToString : full:bool -> string
  member CustomAttributes : Expr list
  member Type : Type
  static member AddressOf : target:Expr -> Expr
  static member AddressSet : target:Expr * value:Expr -> Expr
  static member Application : functionExpr:Expr * argument:Expr -> Expr
  static member Applications : functionExpr:Expr * arguments:Expr list list -> Expr
  ...

Full name: Microsoft.FSharp.Quotations.Expr

--------------------
type Expr<'T> =
  inherit Expr
  member Raw : Expr

Full name: Microsoft.FSharp.Quotations.Expr<_>

type bool = Boolean

Full name: Microsoft.FSharp.Core.bool

val isPure : s:Sem -> bool

Full name: Script.isPure

determines if expression is guaranteed to evaluate without side-effects

val s : Sem

val v : Var

val not : value:bool -> bool

Full name: Microsoft.FSharp.Core.Operators.not

property Var.IsMutable: bool

val b : Sem

val k : Sem

val fs : Sem list

Multiple items
module List

from Microsoft.FSharp.Collections

--------------------
type List<'T> =
  | ( [] )
  | ( :: ) of Head: 'T * Tail: 'T list
  interface IEnumerable
  interface IEnumerable<'T>
  member GetSlice : startIndex:int option * endIndex:int option -> 'T list
  member Head : 'T
  member IsEmpty : bool
  member Item : index:int -> 'T with get
  member Length : int
  member Tail : 'T list
  static member Cons : head:'T * tail:'T list -> 'T list
  static member Empty : 'T list

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

val forall : predicate:('T -> bool) -> list:'T list -> bool

Full name: Microsoft.FSharp.Collections.List.forall

val isPureNode : bool

val args : Sem list

val getType : reflect:bool -> s:Sem -> Type

Full name: Script.getType

val reflect : bool

union case Option.None: Option<'T>

property Var.Type: Type

union case Option.Some: Value: 'T -> Option<'T>

val t : Type

val o : obj

Object.GetType() : Type

type FSharpType =
  static member GetExceptionFields : exceptionType:Type * ?bindingFlags:BindingFlags -> PropertyInfo []
  static member GetFunctionElements : functionType:Type -> Type * Type
  static member GetRecordFields : recordType:Type * ?bindingFlags:BindingFlags -> PropertyInfo []
  static member GetTupleElements : tupleType:Type -> Type []
  static member GetUnionCases : unionType:Type * ?bindingFlags:BindingFlags -> UnionCaseInfo []
  static member IsExceptionRepresentation : exceptionType:Type * ?bindingFlags:BindingFlags -> bool
  static member IsFunction : typ:Type -> bool
  static member IsModule : typ:Type -> bool
  static member IsRecord : typ:Type * ?bindingFlags:BindingFlags -> bool
  static member IsTuple : typ:Type -> bool
  ...

Full name: Microsoft.FSharp.Reflection.FSharpType

static member FSharpType.MakeFunctionType : domain:Type * range:Type -> Type

val uci : UnionCaseInfo

property UnionCaseInfo.DeclaringType: Type

val mi : MethodInfo

property MethodInfo.ReturnType: Type

val e : Expr

property Expr.Type: Type

val isSubtypeOf : iface:Type -> ty:Type -> bool

Full name: Script.isSubtypeOf

determines if the two types are in a subtype relationship

val iface : Type

val ty : Type

val proj : (Type -> Assembly * string * string * int)

property Type.Assembly: Assembly

property Type.Namespace: string

property MemberInfo.Name: string

property MemberInfo.MetadataToken: int

Type.IsAssignableFrom(c: Type) : bool

Type.GetInterfaces() : Type []

type Array =
  member Clone : unit -> obj
  member CopyTo : array:Array * index:int -> unit + 1 overload
  member GetEnumerator : unit -> IEnumerator
  member GetLength : dimension:int -> int
  member GetLongLength : dimension:int -> int64
  member GetLowerBound : dimension:int -> int
  member GetUpperBound : dimension:int -> int
  member GetValue : [<ParamArray>] indices:int[] -> obj + 7 overloads
  member Initialize : unit -> unit
  member IsFixedSize : bool
  ...

Full name: System.Array

val exists : predicate:('T -> bool) -> array:'T [] -> bool

Full name: Microsoft.FSharp.Collections.Array.exists

val if0 : Type

property Type.BaseType: Type

val bt : Type

val containsReference : v:Var -> s:Sem -> bool

Full name: Script.containsReference

val w : Var

val exists : predicate:('T -> bool) -> list:'T list -> bool

Full name: Microsoft.FSharp.Collections.List.exists

type Environment = Map<Var,Sem>

Full name: Script.Environment

Multiple items
module Map

from Microsoft.FSharp.Collections

--------------------
type Map<'Key,'Value (requires comparison)> =
  interface IEnumerable
  interface IComparable
  interface IEnumerable<KeyValuePair<'Key,'Value>>
  interface ICollection<KeyValuePair<'Key,'Value>>
  interface IDictionary<'Key,'Value>
  new : elements:seq<'Key * 'Value> -> Map<'Key,'Value>
  member Add : key:'Key * value:'Value -> Map<'Key,'Value>
  member ContainsKey : key:'Key -> bool
  override Equals : obj -> bool
  member Remove : key:'Key -> Map<'Key,'Value>
  ...

Full name: Microsoft.FSharp.Collections.Map<_,_>

--------------------
new : elements:seq<'Key * 'Value> -> Map<'Key,'Value>

val meaning : env:Environment -> expr:Expr -> Sem

Full name: Script.meaning

Maps syntactic trees to semantic expressions; apply optimizations as required

val env : Environment

val expr : Expr

val mkLit : ('T -> Sem)

val x : 'T

val typeof<'T> : Type

Full name: Microsoft.FSharp.Core.Operators.typeof

val mkLet : (Var -> Sem -> Sem -> Sem)

val sbind : Sem

val skont : Sem

val fallback : (Environment -> Expr -> Sem)

active recognizer ShapeCombination: Expr -> Choice<Var,(Var * Expr),(obj * Expr list)>

Full name: Microsoft.FSharp.Quotations.ExprShape.( |ShapeVar|ShapeLambda|ShapeCombination| )

val shape : obj

val args : Expr list

val sargs : Sem list

val map : mapping:('T -> 'U) -> list:'T list -> 'U list

Full name: Microsoft.FSharp.Collections.List.map

active recognizer IfThenElse: Expr -> (Expr * Expr * Expr) option

Full name: Microsoft.FSharp.Quotations.Patterns.( |IfThenElse|_| )

active recognizer TupleGet: Expr -> (Expr * int) option

Full name: Microsoft.FSharp.Quotations.Patterns.( |TupleGet|_| )

active recognizer TypeTest: Expr -> (Expr * Type) option

Full name: Microsoft.FSharp.Quotations.Patterns.( |TypeTest|_| )

active recognizer UnionCaseTest: Expr -> (Expr * UnionCaseInfo) option

Full name: Microsoft.FSharp.Quotations.Patterns.( |UnionCaseTest|_| )

active recognizer LetRecursive: Expr -> ((Var * Expr) list * Expr) option

Full name: Microsoft.FSharp.Quotations.Patterns.( |LetRecursive|_| )

active recognizer QuoteRaw: Expr -> Expr option

Full name: Microsoft.FSharp.Quotations.Patterns.( |QuoteRaw|_| )

active recognizer QuoteTyped: Expr -> Expr option

Full name: Microsoft.FSharp.Quotations.Patterns.( |QuoteTyped|_| )

active recognizer PropertyGet: Expr -> (Expr option * PropertyInfo * Expr list) option

Full name: Microsoft.FSharp.Quotations.Patterns.( |PropertyGet|_| )

static member FSharpType.IsRecord : typ:Type * ?allowAccessToPrivateRepresentation:bool -> bool
static member FSharpType.IsRecord : typ:Type * ?bindingFlags:BindingFlags -> bool

static member FSharpType.IsUnion : typ:Type * ?allowAccessToPrivateRepresentation:bool -> bool
static member FSharpType.IsUnion : typ:Type * ?bindingFlags:BindingFlags -> bool

static member FSharpType.IsTuple : typ:Type -> bool

active recognizer ShapeVar: Expr -> Choice<Var,(Var * Expr),(obj * Expr list)>

Full name: Microsoft.FSharp.Quotations.ExprShape.( |ShapeVar|ShapeLambda|ShapeCombination| )

active recognizer ShapeLambda: Expr -> Choice<Var,(Var * Expr),(obj * Expr list)>

Full name: Microsoft.FSharp.Quotations.ExprShape.( |ShapeVar|ShapeLambda|ShapeCombination| )

val failwith : message:string -> 'T

Full name: Microsoft.FSharp.Core.Operators.failwith

active recognizer Value: Expr -> (obj * Type) option

Full name: Microsoft.FSharp.Quotations.Patterns.( |Value|_| )

member Map.TryFind : key:'Key -> 'Value option

val sopt : Sem option

active recognizer Lambda: Expr -> (Var * Expr) option

Full name: Microsoft.FSharp.Quotations.Patterns.( |Lambda|_| )

val body : Expr

val slam : (Sem -> Sem)

member Map.Add : key:'Key * value:'Value -> Map<'Key,'Value>

active recognizer Application: Expr -> (Expr * Expr) option

Full name: Microsoft.FSharp.Quotations.Patterns.( |Application|_| )

val f : Expr

val g : Expr

active recognizer Deref: Sem -> Sem

val lam : (Sem -> Sem)

active recognizer Let: Expr -> (Var * Expr * Expr) option

Full name: Microsoft.FSharp.Quotations.Patterns.( |Let|_| )

val bind : Expr

val kont : Expr

val x : Var

val cond : Expr

val ifExpr : Expr

val elseExpr : Expr

val ccond : bool

val branch : Expr

active recognizer Sequential: Expr -> (Expr * Expr) option

Full name: Microsoft.FSharp.Quotations.Patterns.( |Sequential|_| )

val left : Expr

val right : Expr

val ls : Sem

active recognizer NewTuple: Expr -> Expr list option

Full name: Microsoft.FSharp.Quotations.Patterns.( |NewTuple|_| )

val ts : Expr list

property Type.IsValueType: bool

val tuple : Expr

val i : int

val ts : Sem list

active recognizer NewRecord: Expr -> (Type * Expr list) option

Full name: Microsoft.FSharp.Quotations.Patterns.( |NewRecord|_| )

val fs : Expr list

val prop : PropertyInfo

static member FSharpType.GetRecordFields : recordType:Type * ?allowAccessToPrivateRepresentation:bool -> PropertyInfo []
static member FSharpType.GetRecordFields : recordType:Type * ?bindingFlags:BindingFlags -> PropertyInfo []

val tryFindIndex : predicate:('T -> bool) -> array:'T [] -> int option

Full name: Microsoft.FSharp.Collections.Array.tryFindIndex

val p : PropertyInfo

member UnionCaseInfo.GetFields : unit -> PropertyInfo []

active recognizer NewUnionCase: Expr -> (UnionCaseInfo * Expr list) option

Full name: Microsoft.FSharp.Quotations.Patterns.( |NewUnionCase|_| )

val uci' : UnionCaseInfo

val st : Type

val staticTypeTestResult : bool option

val r : bool

static member Expr.Sequential : first:Expr * second:Expr -> Expr

static member Expr.Value : value:'T -> Expr
static member Expr.Value : value:obj * expressionType:Type -> Expr

active recognizer Coerce: Expr -> (Expr * Type) option

Full name: Microsoft.FSharp.Quotations.Patterns.( |Coerce|_| )

val tryDeref : (Sem -> Sem option)

val v : Sem

val r : Sem option

active recognizer SpecificCall: Expr -> Expr -> (Expr option * Type list * Expr list) option

Full name: Microsoft.FSharp.Quotations.DerivedPatterns.( |SpecificCall|_| )

val value : Expr

val isNull : value:'T -> bool (requires 'T : null)

Full name: Microsoft.FSharp.Core.Operators.isNull

val x : obj

Object.ReferenceEquals(objA: obj, objB: obj) : bool

val func : Expr

static member Expr.Application : functionExpr:Expr * argument:Expr -> Expr

val fst : tuple:('T1 * 'T2) -> 'T1

Full name: Microsoft.FSharp.Core.Operators.fst

val t : Expr

static member Expr.TupleGet : tuple:Expr * index:int -> Expr

val snd : tuple:('T1 * 'T2) -> 'T2

Full name: Microsoft.FSharp.Core.Operators.snd

val ignore : value:'T -> unit

Full name: Microsoft.FSharp.Core.Operators.ignore

val box : value:'T -> obj

Full name: Microsoft.FSharp.Core.Operators.box

module LanguagePrimitives

from Microsoft.FSharp.Core

module IntrinsicFunctions

from Microsoft.FSharp.Core.LanguagePrimitives

val unbox : value:obj -> 'T

Full name: Microsoft.FSharp.Core.Operators.unbox

static member Expr.Coerce : source:Expr * target:Type -> Expr

active recognizer Call: Expr -> (Expr option * MethodInfo * Expr list) option

Full name: Microsoft.FSharp.Quotations.Patterns.( |Call|_| )

property MemberInfo.DeclaringType: Type

property Type.FullName: string

String.StartsWith(value: string) : bool
String.StartsWith(value: string, comparisonType: StringComparison) : bool
String.StartsWith(value: string, ignoreCase: bool, culture: Globalization.CultureInfo) : bool

val literals : obj []

module Seq

from Microsoft.FSharp.Collections

val choose : chooser:('T -> 'U option) -> source:seq<'T> -> seq<'U>

Full name: Microsoft.FSharp.Collections.Seq.choose

val toArray : source:seq<'T> -> 'T []

Full name: Microsoft.FSharp.Collections.Seq.toArray

property Array.Length: int

property List.Length: int

MethodBase.Invoke(obj: obj, parameters: obj []) : obj
MethodBase.Invoke(obj: obj, invokeAttr: BindingFlags, binder: Binder, parameters: obj [], culture: Globalization.CultureInfo) : obj

Multiple items
type TargetInvocationException =
inherit ApplicationException
new : inner:Exception -> TargetInvocationException + 1 overload

Full name: System.Reflection.TargetInvocationException

--------------------
TargetInvocationException(inner: exn) : unit
TargetInvocationException(message: string, inner: exn) : unit

val e : TargetInvocationException

property Exception.InnerException: exn

Multiple items
type NotSupportedException =
inherit SystemException
new : unit -> NotSupportedException + 2 overloads

Full name: System.NotSupportedException

--------------------
NotSupportedException() : unit
NotSupportedException(message: string) : unit
NotSupportedException(message: string, innerException: exn) : unit

val reify : s:Sem -> Expr

Full name: Script.reify

Maps semantic expressions back to a syntactic representation

static member Expr.Var : variable:Var -> Expr

static member Expr.Lambda : parameter:Var * body:Expr -> Expr

static member Expr.Let : letVariable:Var * letExpr:Expr * body:Expr -> Expr

static member Expr.NewTuple : elements:Expr list -> Expr

static member Expr.NewRecord : recordType:Type * elements:Expr list -> Expr

static member Expr.NewUnionCase : unionCase:UnionCaseInfo * arguments:Expr list -> Expr

val mI : MethodInfo

static member Expr.Call : methodInfo:MethodInfo * arguments:Expr list -> Expr
static member Expr.Call : obj:Expr * methodInfo:MethodInfo * arguments:Expr list -> Expr

val sparams : Sem list

val RebuildShapeCombination : shape:obj * arguments:Expr list -> Expr

Full name: Microsoft.FSharp.Quotations.ExprShape.RebuildShapeCombination

val nbe : e:Expr<'a> -> Expr<'a>

Full name: Script.nbe

Apply normalization-by-evaluation to quotation tree

val e : Expr<'a>

val empty<'Key,'T (requires comparison)> : Map<'Key,'T> (requires comparison)

Full name: Microsoft.FSharp.Collections.Map.empty

static member Expr.Cast : source:Expr -> Expr<'T>

val nbe_decompile : expr:Expr<'a> -> string

Full name: Script.nbe_decompile

val expr : Expr<'a>

namespace Swensen

namespace Swensen.Unquote

module Operators

from Swensen.Unquote

val decompile : expr:Expr -> string

Full name: Swensen.Unquote.Operators.decompile

val f : (int option -> bool)

val x : int option

val mutable y : int

val f : (int -> int)

val x : int

val z : int

val f : (int -> unit)

type Console =
  static member BackgroundColor : ConsoleColor with get, set
  static member Beep : unit -> unit + 1 overload
  static member BufferHeight : int with get, set
  static member BufferWidth : int with get, set
  static member CapsLock : bool
  static member Clear : unit -> unit
  static member CursorLeft : int with get, set
  static member CursorSize : int with get, set
  static member CursorTop : int with get, set
  static member CursorVisible : bool with get, set
  ...

Full name: System.Console

Console.WriteLine() : unit
   (+0 other overloads)
Console.WriteLine(value: string) : unit
   (+0 other overloads)
Console.WriteLine(value: obj) : unit
   (+0 other overloads)
Console.WriteLine(value: uint64) : unit
   (+0 other overloads)
Console.WriteLine(value: int64) : unit
   (+0 other overloads)
Console.WriteLine(value: uint32) : unit
   (+0 other overloads)
Console.WriteLine(value: int) : unit
   (+0 other overloads)
Console.WriteLine(value: float32) : unit
   (+0 other overloads)
Console.WriteLine(value: float) : unit
   (+0 other overloads)
Console.WriteLine(value: decimal) : unit
   (+0 other overloads)

type Stream<'T> = ('T -> unit) -> unit

Full name: Script.Stream<_>

type unit = Unit

Full name: Microsoft.FSharp.Core.unit

val ofArray : (int [] -> (int -> unit) -> unit)

val xs : int []

Multiple items
val int : value:'T -> int (requires member op_Explicit)

Full name: Microsoft.FSharp.Core.Operators.int

--------------------
type int = int32

Full name: Microsoft.FSharp.Core.int

--------------------
type int<'Measure> = int

Full name: Microsoft.FSharp.Core.int<_>

val k : (int -> unit)

val map : ((int -> int) -> Stream<int> -> Stream<int>)

val ts : Stream<int>

val t : int

val filter : ((int -> bool) -> Stream<int> -> Stream<int>)

val f : (int -> bool)

val iter : ((int -> unit) -> Stream<int> -> unit)

val printfn : format:Printf.TextWriterFormat<'T> -> 'T

Full name: Microsoft.FSharp.Core.ExtraTopLevelOperators.printfn

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More information

Link:	http://fssnip.net/7Xn
Posted:	4 years ago
Author:	Eirik Tsarpalis
Tags:	metaprogramming , quotations