Back to Questions
1.2k
views4
comments
Compiler crash "Not in JavaScript form"
websharper

Got the below message. I will try to create a minimum source example for it.

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25

Global error 'Not in JavaScript form: DoNotReturn' at
   at WebSharper.Compiler.JavaScriptWriter.transformStatement@349-14.Invoke(String message)
   at WebSharper.Compiler.JavaScriptWriter.transformStatement(Environment env, Statement statement)
   at WebSharper.Compiler.JavaScriptWriter.add@268.Invoke(Statement a)
   at Microsoft.FSharp.Primitives.Basics.List.iter[T](FSharpFunc'2 f, FSharpList'1 x)
   at WebSharper.Compiler.JavaScriptWriter.flatten@265(Environment env, FSharpList'1 s)
   at WebSharper.Compiler.JavaScriptWriter.transformStatement(Environment env, Statement statement)
   at WebSharper.Compiler.JavaScriptWriter.transformStatement(Environment env, Statement statement)
   at WebSharper.Compiler.JavaScriptWriter.transformStatement(Environment env, Statement statement)
   at WebSharper.Compiler.JavaScriptWriter.transformExpr(Environment env, Expression expr)
   at WebSharper.Compiler.JavaScriptWriter.transformExpr(Environment env, Expression expr)
   at WebSharper.Compiler.JavaScriptWriter.transformStatement(Environment env, Statement statement)
   at WebSharper.Compiler.JavaScriptWriter.add@268.Invoke(Statement a)
   at Microsoft.FSharp.Primitives.Basics.List.iter[T](FSharpFunc'2 f, FSharpList'1 x)
   at WebSharper.Compiler.JavaScriptWriter.flatten@265(Environment env, FSharpList'1 s)
   at WebSharper.Compiler.JavaScriptWriter.transformStatement(Environment env, Statement statement)
   at WebSharper.Compiler.JavaScriptWriter.transformExpr(Environment env, Expression expr)
   at WebSharper.Compiler.JavaScriptWriter.transformExpr(Environment env, Expression expr)
   at WebSharper.Compiler.Packager.exprToString(Preferences pref, FSharpFunc'2 getWriter, Expression statement)
   at WebSharper.Compiler.FrontEnd.CreateResources(FSharpOption'1 comp, Info refMeta, Info current, Boolean sourceMap, FSharpOption'1 closures, AssemblyDefinition a)
   at WebSharper.Compiler.FrontEnd.ModifyCecilAssembly(FSharpOption'1 comp, Info refMeta, Info current, Boolean sourceMap, FSharpOption'1 closures, AssemblyDefinition a)
   at WebSharper.FSharp.Program.Compile$cont@164-2(WsConfig config, Loader loader, Task'1 refMeta, Compilation comp, Unit unitVar)
   at WebSharper.FSharp.Program.Compile$cont@58(WsConfig config, WarnSettings warnSettings, String thisName, Unit unitVar)
   at WebSharper.FSharp.Program.compileMain$cont@207(String[] argv, Unit unitVar)
   at WebSharper.FSharp.Program.main(String[] argv)
.

Hi, thanks for the report!

A new version will be out soon that can report transformation errors at the source position, not a global error inside JavaScript writer. Still, can you find the offending part? It seems like a bug in F# tail recursion optimizer, that uses DoNotReturn to annotate a tail call position, so it is some tail recursive function.

By on 9/15/2017 4:57 AM ()

Yes, I just also found out that it has to do with recursion and continuation functions. Here is my minimum example:

1
2
3
4
5
6
7
8
9

namespace Test

open WebSharper

[<JavaScript>]
module Test =
    type N = A of N | B

    let rec f = function A x -> f x | B -> true
By on 9/15/2017 6:07 AM ()

Which package versions are you using? I'm not getting this error on any WebSharper.4.0-rc releases (the first of which is the same as latest Zafir-beta10.

By on 9/15/2017 7:44 AM ()

I was still on beta-9. Indeed works with beta-10. Sorry for bothering your.

By on 9/15/2017 8:52 AM ()

    Topic tags

    IntelliFactory Offices Copyright (c) 2011-2012 IntelliFactory. All rights reserved.
    Home | Products | Consulting | Trainings | Blogs | Jobs | Contact Us | Terms of Use | Privacy Policy | Cookie Policy     		Built with WebSharper