I have the following code:
#r "../packages/FSharp.Data.2.0.9/lib/portable-net40+sl5+wp8+win8/FSharp.Data.dll"
open FSharp.Data
let trainData = CsvFile.Load("../resources/Train.csv")
let rowCount = trainData.Rows |> Seq.length
And I am getting this exception
System.Exception: Only web locations are supported
I am using VS2012. Has anyone seen this before?
I changed it to
#r "../packages/FSharp.Data.2.0.9/lib/net40/FSharp.Data.dll"
and it worked
Hope this helps someone
Related
New F# Program
Add nuget package FSharp.Data
Attempt to run this code
open FSharp.Data
let doc = #"<!DOCTYPE html><html><body><p>FSharp!</p></body></html>" |> Encoding.UTF8.GetBytes |> MemoryStream |> HtmlDocument.Load
CssSelectorExtensions.CssSelect (doc, "p") |> LINQPad.Extensions.Dump
The execution of the CssSelect function throws the error
Method not found: 'Microsoft.FSharp.Collections.FSharpList`1<FSharp.Data.HtmlNode> CssSelectorExtensions.CssSelect(FSharp.Data.HtmlDocument, System.String)'.
Same error in both LinqPad 5 and 6.
Code runs fine in VS 2019 (without the Dump function obviously)
Can anyone repo ? Why the error in LinqPad ?
Adding FSharp.Core from nuget to the query got rid of the error
I am working through the Embedding F# Interactive example from http://fsharp.github.io/FSharp.Compiler.Service/interactive.html but am having an issue with the following line throwing an exception:
let fsiSession = FsiEvaluationSession.Create(fsiConfig, allArgs, inStream, outStream, errStream)
The exception thrown is:
"An unhandled exception of type 'System.Exception' occurred in FSharp.Compiler.Service.dll
Additional information: Error creating evaluation session: StopProcessing null"
My project is being run from VS2015 Enterprise Update 1, setup as a simple F# console app, with Target F# runtime being F# 4.0 with the Target Framework as 4.6. The version of FSharp.Compiler.Service downloaded from nuget is 2.0.0.2.
The Program.Fs file code I am running is here (a direct port of the example):
open System
open System.IO
open System.Text
open Microsoft.FSharp.Compiler.SourceCodeServices
open Microsoft.FSharp.Compiler.Interactive.Shell
[<EntryPoint>]
let main argv =
let sbOut = new StringBuilder()
let sbErr = new StringBuilder()
let inStream = new StringReader("")
let outStream = new StringWriter(sbOut)
let errStream = new StringWriter(sbErr)
// Build command line arguments & start FSI session
let argv = [| "C:\\fsi.exe" |]
let allArgs = Array.append argv [|"--noninteractive"|]
let fsiConfig = FsiEvaluationSession.GetDefaultConfiguration()
let fsiSession = FsiEvaluationSession.Create(fsiConfig, allArgs, inStream, outStream, errStream)
/// Evaluate expression & return the result
let evalExpression text =
match fsiSession.EvalExpression(text) with
| Some value -> printfn "%A" value.ReflectionValue
| None -> printfn "Got no result!"
evalExpression "42+1" // prints '43'
Console.ReadLine() |> ignore
0 // return integer
Any thoughts would be appreciated.
The key to your problem is found at Compiler Services: Notes on FSharp.Core.dll
If doing dynamic compilation and execution you may also need to
include an FSharp.Core.optdata and FSharp.Core.sigdata, see below for
guidance.
When you build the application the output directory with FSharp.Core.dll is missing two files:
FSharp.Core.optdata
FSharp.Core.sigdata
You will need to find these two files and the correct versions of the files that agree with FSharp.Core.dll and copy them to the build output directory.
How to find the files using Visual Studio
From menu View -> Solution Explorer
Expand Project
Expand References
Right click FSharp.Core and select properties.
The Full Path gives the directory that should have at least the three files.
Use a file explorer to open the directory in Full Path.
Copy the two files
FSharp.Core.optdata
FSharp.Core.sigdata
to the build directory.
How to find the build directory using Visual Studio
From menu View -> Solution Explorer
Select Project
Press F4 to open the Properties Page
The Project Folder with \bin\Debug is the default when debugging with VS.
Change location of fsi.exe
Now that you have the two needed files you will also need to change the location of fsi.exe
let argv = [| "C:\\fsi.exe" |]
because I doubt that fsi.exe is in the root of your C drive.
I am trying to set up a tiny F# console app with FSharp.Data referenced in the solution. I got the following error at runtime :
An unhandled exception of type 'System.TypeInitializationException' occurred in Anot_F1.exe
for this code (error in line 4) :
1 open FSharp.Data
2 type Anot_lines = CsvProvider<"anot1.csv",Separators=";">
3 let ll = Anot_lines.Load("anot1.csv")
4 for r in ll.Rows do
5 printfn "%A" r.ToString
In debug mode after line 3, I can see that the variable ll contains the proper Headers but does not show the rows.
My CSV file is :
tline;tcol;bline;bcol;anot
3;1;4;16;"Barack Obama has ... The US president"
3;1;3;12;"Barack Obama"
3;18;3;26;"ratcheted"
4;102;4;109;"agencies"
4;289;4;306;"financial pressure"
4;1;4;320;"The US president ...ure on the regime"
4;1;4;16;"The US president"
I am new to F# and especially have no experience on using type providers.
Any help greatly appreciated.
The issue is with line 3, you're using a method that loads CSV data from a URL. You need to use the GetSample() method. Also note that the "%A" format placeholder can print any value and doesn't require a ToString() call.
let ll = Anot_lines.GetSample()
for r in ll.Rows do
printfn "%A" r
I'm trying to use the JsonProvider and I'm getting the following error when I call a function on it:
System.TypeInitializationException was unhandled
Message: An unhandled exception of type 'System.TypeInitializationException' occurred in PortableLibrary1.dll
Additional information: The type initializer for '<StartupCode$PortableLibrary1>.$PortableLibrary1' threw an exception.
I have a basic console application as follows:
module Pinit =
open FSharp.Data
type JsonT = JsonProvider<"""..\myFile.json""">
let doc = JsonT.Load("""..\nyFile.json""")
let result = doc.GeneratedAt
[<EntryPoint>]
let main argv =
printfn "%A" Pinit.doc.GeneratedAt
0
When run within the ConsoleApplication it all works as expected.
If I create an F# Portable Class library as follows:
module Pinit =
open FSharp.Data
type JsonT = JsonProvider<"""..\myFile.json""">
let doc = JsonT.Load("""..\nyFile.json""")
let result = doc.GeneratedAt
Create another Console Application and reference that Portable Class Library and call the code as follows:
open PortableLibrary1
[<EntryPoint>]
let main argv =
printfn "%A" Pinit.result
0
When I run the program then it generates the exception defined above:
I'm suspecting it's because of the versions of FSharp.Core but was wondering whether I was doing something wrong or whether there was a way to get this to work?
Versions:
-- ConsoleApplication --
FSharp.Core = 4.3.1.0
-- PortableClassLibrary --
FSharp.Core = 3.3.1.0
FSharp.Data = NuGet Version: 2.0.0
let bindings are compiled into static members, and in .NET when you have an exception in a static initializer the real exception is masqueraded.
If you turn that into a function call by changing to let result() = doc.GeneratedAt and printfn "%A" (Pinit.result()) you'll get the real exception:
Only web locations are supported
Portable profiles don't support accessing the file system. So inside the PCL you can either have web urls or load manually from an embedded resource. See here for an example: https://github.com/ovatsus/Apps/blob/master/Trains/Stations.fs#L65. Or you can load the file with File.ReadAllText in the console project and pass it to the PCL.
This was with a Portable Profile (Legacy) project, which is Profile 47 (and FSharp.Core 2.3.6.0). I then also tested with a Portable Profile project, which is Profile 7 (and FSharp.Core 3.3), and noticed it's not working correctly, it's giving this exception instead
Method not found: 'FSharp.Data.Runtime.JsonValueOptionAndPath FSharp.Data.Runtime.JsonRuntime.TryGetPropertyUnpackedWithPath(FSharp.Data.Runtime.IJsonDocument, System.String)'.
I created a github issue to track that: https://github.com/fsharp/FSharp.Data/issues/521
I am getting this when trying to parse a simple csv string. I am running F# out of VS 2013, the dll says it is version 4.3.0.1 which I thought was F# 3.1. My Fsharp.Data dll is 1.1.10.
I am trying to run this as part of an nunit test using resharper. The snippet does work in interactive mode.
Here is the code:
open FSharp.Data
type TestCsv = CsvProvider<"test,taht\n1,1">
let x = TestCsv.Parse "test,taht\n1,1"
let tests = x.Data |> Seq.map (fun x -> x.test)
tests |> Seq.head
And the result:
System.Exception : Couldn't parse row 1 according to schema: Method not found: 'Microsoft.FSharp.Core.FSharpOption`1<System.String> FSharp.Data.RuntimeImplementation.Operations.AsOption(System.String)'.
Any ideas how to fix this?
FSharp.Data 1.1.10 doesn't support F# 3.1/VS2013. Please try with the prerelease version 2.0.0-alpha3 and let us if that works. Make sure both the unit test project and the library project are using the same version of FSharp.Core (either 4.3.0.0 or 4.3.1.0)