Yaaf.FSharp.Scripting
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NuGet
PM> Install-Package Yaaf.FSharp.Scripting
Include as source file
Paket
You can include the functionality directly into your application by using paket source files:
paket.dependencies:
github matthid/Yaaf.FSharp.Scripting src/source/Yaaf.FSharp.Scripting/YaafFSharpScripting.fs
paket.references:
File: YaafFSharpScripting.fs
See http://fsprojects.github.io/Paket/github-dependencies.html for details.
NuGet
The YaafFSharpScripting.fs source code file is included in the nuget package as well.
You can find it in content/YaafFSharpScripting.fs.
By adding the source code file (as reference) to your project you don't need
to add a nuget dependency (Yaaf.FSharp.Scripting) to your final package.
Quick intro
This library tries to improve the scripting capabilities of FSharp.
It builds on top of FSharp.Compiler.Service but provides a nice an clean API:
open Yaaf.FSharp.Scripting
use fsiSession = ScriptHost.CreateNew()
fsiSession.Reference (@"C:\MyAssembly.dll")
fsiSession.Open ("MyAssembly")
// hook 25 into the session with name test (ie "let test = 25")
// this works with any object
fsiSession.Let "test" 25
// Get a value out of the evaluator
let v = fsiSession.EvalExpression<int> "test"
assert (v = 25)
// Try to get a value (with handling error cases)
match fsiSession.Handle<int> fsiSession.EvalExpression "test" with
| InvalidExpressionType e ->
// not of type int
// e.Value contains the result object, e.ExpectedType the expected type (int in this case)
()
| InvalidCode e ->
// couldn't get app value (compiler error, not defined or exception in the running code)
// e.Input is the given text, e.Result is the compiler or the script output
// Note: script exceptions are written as strings within e.Result
()
| Result r ->
// r is the value.
()
// Get the output of the snippet
let v = fsiSession.EvalInteractionWithOutput """printf "test" """
assert (v.Output.ScriptOutput = "test")
// Get the error message of the compilation
try fsiSession.EvalInteraction """ Some_Invalid_F# """
with :? FsiEvaluationException ev ->
printfn "FSI said: %s" ev.Result.Error.FsiOutput
printfn "Complete Error: %O" ev
// Load scripts
fsiSession.EvalScript "Script.fsx"
The library also provides some nice members which are missing in FSharp.Compiler.Service:
open Yaaf.FSharp.Scripting
open Microsoft.FSharp.Compiler.SourceCodeServices
// A Assembly -> FSharpEntity mapping (extension) function
let fsAssembly = FSharpAssembly.FromAssembly typeof<MyType>.Assembly
// A extension method to find the entity type
let fsType = fsAssembly.Value.FindType typeof<MyType>And some extensions for System.Type to get the FSharp type name
// with concrete types.
let def = typeof<option<int>>
test <@ def.Name = "FSharpOption`1" @>
test <@ def.Namespace = "Microsoft.FSharp.Core" @>
test <@ def.FSharpParamList = "<System.Int32>" @>
test <@ def.FSharpFullName = "Microsoft.FSharp.Core.Option" @>
test <@ def.FSharpFullNameWithTypeArgs = "Microsoft.FSharp.Core.Option<System.Int32>" @>
test <@ def.FSharpName = "Option" @>
// With typedefs.
let def = typedefof<option<int>>
test <@ def.Name = "FSharpOption`1" @>
test <@ def.FullName = "Microsoft.FSharp.Core.FSharpOption`1" @>
test <@ def.FSharpParamList = "<_>" @>
test <@ def.FSharpFullName = "Microsoft.FSharp.Core.Option" @>
test <@ def.FSharpFullNameWithTypeArgs = "Microsoft.FSharp.Core.Option<_>" @>
test <@ def.FSharpName = "Option" @>
