Problems when trying to run FParsec in F# Interactive

Question

I'm trying to run some FParsec code in F# Interactive but with no success. I am able to build and run this tutorial.fs file, but the same isn't happening with FSI, as it didn't recognize FParsec.dll.

I've already tried running the #r "Parsec" command in FSI but it was of no avail.

Anyone has a clue on what might be the problem here?

Fallfish

Answer 1

FParsec is not GAC installed, therefore you need to put the full path to the dll in the #r directive, not just the name of the assembly. Also, don't forget that "...FParsec is built as two DLLs. The C# bits are compiled into the FParsecCS.dll and the F# bits (which depend on the C# bits) are compiled into FParsec.dll." (section 3.2 of the documentation). e.g.

#r @"C:\FParsecCS.dll"
#r @"C:\FParsec.dll"

Paralipomena

I was sure I had tried it with the full path, too. Seems I was mistaken. – Fallfish

If you are always using the dll you can add it to FSI automatically via the command line with -r "C:\Fparsec.dll". The option is hiding in the FSI options in visual studio – Nodule

Also, be sure you reference FParsecCS before FParsec, otherwise you'll get an error FS0074. – Leboeuf

Reset the Interactive after every script change. – Spectrometer

In visual studio, to reset the interactive F# window, right-click anywhere in the F# interactive window -> "Reset Interactive Session" – Lienlienhard