The quotationcompiler from manofstick

quotationcompiler's Introduction

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.

Example

#r "QuotationCompiler.dll"

open QuotationCompiler

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

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

Library	Compilation time (cold)	Compilation time (warm)
Native	N/A	N/A
Unquote	00:00:00.055	00:00:00.000
FSharp.Quotations.Evaluator	00:00:00.405	00:00:00.003
QuotationCompiler	00:00:05.068	00:00:00.161

Executing the compiled functions 10^6 times produced the following results:

Library	Execution time	GC gen0,1,2
Native	00:00:00.053	0,0,0
Unquote	00:01:46.675	9598,12,1
FSharp.Quotations.Evaluator	00:00:00.087	15,0,0
QuotationCompiler	00:00:00.053	0,0,0

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 or CompiledName types.