CsvProvider - Error: Attempted to access an element as a type incompatible with the array.

[petarvucetin]

I have a very simple file that is failing to load. The only way to make it work is to add another column.

val it : CsvProvider<...> =
FSharp.Data.Runtime.CsvFile1[System.Tuple1[System.String]]
{Headers = Some [|"Tag"|];
NumberOfColumns = 1;
Quote = '"';
Rows = Error: Attempted to access an element as a type incompatible with the array.;
Separators = ",";}

dummy.zip

[tpetricek]

I tried to load the file using CsvProvider and did not get any error. Here is what I tried (in a script file):

#r "packages/FSharp.Data/lib/net40/FSharp.Data.dll"
open FSharp.Data

type C = CsvProvider<"C:/temp/dummy.csv">
for r in C.GetSample().Rows do
  printfn "%s" r.Tag

Could you share your F# code? Perhaps I'm using it differently than you are...

One possible reason for the error that I've seen before is when you use relative path as an argument to the CSV type provider - this may sometimes confuse F# Interactive (the editor thinks it is fine, but F# Interactive thinks it is in another folder and fails to find the file when running the type provider).

One fix for this is to use __SOURCE_DIRECTORY__ like this:

let [<Literal>] Dummy = __SOURCE_DIRECTORY__ + "/dummy.csv"
type C = CsvProvider<Dummy>

This way, the path passed to the CSV provider is a full path and it is more robust.