QuotationCompiler

A small library for compiling code quotations using the F# compiler service. Its primary functionality is transforming quotation trees to untyped ASTs used by the F# compiler. Since code is generated using the F# compiler proper, the end result is fully efficient and optimized.

Package available on NuGet.

Example

#r "QuotationCompiler.dll"

open QuotationCompiler

let hello : unit -> unit = QuotationCompiler.ToFunc <@ printfn "Hello, world!" @> |> Async.RunSynchronously

hello ()

Performance

As can be expected, performance exceeds all other quotation evaluation libraries. Here is a benchmark for a tail recursive algorithm:

[<ReflectedDefinition>]
let sqrt (x : float) =
    let epsilon = 1e-10
    let rec approximate (y : float) =
        let y' = (y + x / y) / 2.
        if abs (y - y') < epsilon then y'
        else
            approximate y'

    approximate x

BenchmarkDotNet=v0.12.0, OS=Windows 10.0.18363
Intel Core i7-8665U CPU 1.90GHz (Coffee Lake), 1 CPU, 8 logical and 4 physical cores
.NET Core SDK=3.1.100-preview3-014645
  [Host]     : .NET Core 3.1.0 (CoreCLR 4.700.19.53102, CoreFX 4.700.19.55104), X64 RyuJIT DEBUG
  DefaultJob : .NET Core 3.1.0 (CoreCLR 4.700.19.53102, CoreFX 4.700.19.55104), X64 RyuJIT

Method	Mean	Error	StdDev	Median	Ratio	RatioSD	Gen 0	Gen 1	Gen 2	Allocated
Managed	2.250 us	0.5888 us	1.718 us	1.300 us	1.00	0.00	-	-	-	-
Unquote	291.363 us	21.7297 us	61.289 us	285.150 us	187.34	100.18	-	-	-	74624 B
FSharp.Quotations.Evaluator	9.622 us	1.9767 us	5.671 us	7.100 us	6.00	4.87	-	-	-	64 B
QuotationCompiler	4.478 us	1.5073 us	4.325 us	1.900 us	2.46	2.78	-	-	-	-

A quicksort implementation benchmark:

Method	Mean	Error	StdDev	Median	Ratio	RatioSD	Gen 0	Gen 1	Gen 2	Allocated
Managed	3.862 us	0.7029 us	2.039 us	2.700 us	1.00	0.00	-	-	-	-
Unquote	10,539.083 us	605.5924 us	1,776.098 us	10,532.100 us	3,364.69	1,415.76	1000.0000	-	-	6318024 B
FSharp.Quotations.Evaluator	112.261 us	5.4346 us	15.680 us	105.100 us	35.54	14.36	-	-	-	6680 B
QuotationCompiler	7.259 us	1.8754 us	5.441 us	4.200 us	2.24	1.92	-	-	-	-

Limitations

The library currently has a few limitations

• No support for dynamic assemblies. Quotations inherently belong to the runtime and ASTs are inherently static. It is impossible to compile quotations that reference types/code defined in F# interactive.
• F# metadata issues. Things may break when referencing generic values, extension methods or CompiledName types.

Build Status

Head (branch master), Build & Unit tests

• Windows
• Linux