F# Editing Support In MonoDevelop and Xamarin Studio
F# C# Other
Latest commit 85c60b4 Sep 23, 2016 @nosami nosami committed on GitHub Update README.md


This repo is now redundant. The F# plugin is now contained within the monodevelop repo

F# Language Support for MonoDevelop / Xamarin Studio

This project contains advanced editing support for the F# addin in MonoDevelop and Xamarin Studio](monodevelop/README.md)


  • Code completion
  • Syntax highlighting
  • Tooltips
  • Debugging
  • Target .NET 3.5, 4.0, 4.5
  • F# Interactive scripting (Alt-Enter execution)
  • Templates (Console Application, Library, Tutorial Project, Gtk Project, iOS, Android)
  • Makefile support
  • Supports F# 3.0 type providers (requires F# 3.0)
  • xbuild support for Visual Studio .fsproj and .sln files without change (requires Mono 3.0 and F# 3.0)

Requires MonoDevelop or Xamarin Studio 4.0.13 and later versions


To use F# language support please ensure that you have F# installed on your system, for details on this please see http://fsharp.org


First check install MonoDevelop/Xamarin Studio. Check if F# support is already installed using the AddIn manager. MonoDevelop/Xamarin Studio --> Add-in manager --> Language Bindings --> Check for F# binding

If so, just use it, no installation is required.

If not, install the F# Language Binding via the AddIn manager.

MonoDevelop/Xamarin Studio --> Add-in manager --> Gallery --> Language Bindings --> F# Language Binding

Building and installing from scratch

Build on Mac/Linux:

Currently this repo is built against the roslyn branch of monodevelop and is actually referenced in the submodules via main/external/fsharbinding. One of the easiest ways of building is to clone monodevelop and work in the submodule directly:

git clone git@github.com:mono/monodevelop -b roslyn --recursive
cd monodevelop
./configure --profile=mac

To configure and compile the addin seperatly then the following commands can be executed from the addin directory (/main/external/fsharpbining if cloning as part of monodevelop)

make install

If MonoDevelop is installed in an unusual prefix you will need to invoke configure.sh with e.g. --prefix=/path/to/prefix/lib/monodevelop. Use ./configure.sh --help to see a list of the paths searched by default.

If you subsequently make changes to the add-in, you will need to make install again and restart MonoDevelop/Xamarin Studio.

The first time you make install the AddIn you'll override Xamarin's official one and it will initially be set to disabled, so you need to go to the AddIn manager and ensure the F# AddIn is enabled.

Note: One thing to check is the the version specified in configure.fsx is higher than the pre-installed version, if it's not then the local addin will not be loaded.

For reference on Mac the locally installed addin is at the following location: /Users/<username>/Library/Application Support/XamarinStudio-6.0/LocalInstall/Addins/fsharpbinding/<version>

Build on Windows (builds and installs the Debug version into Xamarin Studio - adjust as needed)


If you subsequently make changes to the add-in, you will need to build-and-install-debug.bat again and restart MonoDevelop/Xamarin Studio.

Can't get it to work?

Don't give up! Add an issue to bugzilla using F# addin as the component name. Your issue will be seen by the developers.

Notes for Developers

Note: The MonoDevelop/Xamarin Studio developers have now incorporated the binding into all releases of MonoDevelop and Xamarin Studio.

To check things are working try a few different things somewhat at random:

  • Check the F# templates are appearing
  • Create a console project (NOTE: retarget it to .NET 4.0 using right-click->options->General)
  • Check there are completion lists in the console project e.g. for 'System.' and 'System.Console.WriteLine(' and 'List.'
  • Check you can build the console project
  • Check you can run the console project
  • Check you can "debug-step-into" the console project
  • Check you can set a break point in the console project
  • Check there are type tips showing when you move the mouse over code identifiers
  • Load an existing .fsproj (e.g. see MonoDevelop.FSharpBinding/tests/projects/...) and check if completion works etc.
  • Run xbuild on a few .fsproj (this is nothing to do with the binding, it is just fsharp/fsharp)

On Windows, the configuration creates the file MonoDevelop.FSharpBinding\MonoDevelop.FSharp.windows.fsproj. Be aware that this is not the original file, which is MonoDevelop.FSharp.fsproj.orig. The windows file is created automatically by the configuration script (configure.bat)

On Mac/Linux, please develop using the 'Makefile' with Mono 3.0 and FSharp 3.1.

To be able to debug the add-in in Xamarin Studio or Monodevelop, invoke ./configure.sh --debug or configure.bat --debug. This adds the necessary .mdb files to the add-in. When configured with --debug you can simply Start debugging in Xamarin Studio. This will launch a debugged instance of Xamarin Studio.

On Mac, if you make changes to the add-in after debugging, you will need to restart Xamarin Studio or MonoDevelop before rebuilding.

Note that you can not build the add-in in release mode when configured with --debug. To build a release build, first ./configure.sh without --debug

On Mac/Linux, if you make changes to the binding, then loss of completion lists etc. can be disturbing and hard to debug. There are some debugging techniques. To launch MonoDevelop you can use the command:

/Applications/MonoDevelop.app/Contents/MacOS/MonoDevelop --new-window --no-redirect

or this command for Xamarin Studio:

"/Applications/Xamarin Studio.app/Contents/MacOS/XamarinStudio" --new-window --no-redirect

to enable some logging you can use


On Windows you can generally use Visual Studio to help develop the binding. You can start Xamarin Studio or MonoDevelop under the debugger using the normal technique:

devenv /debugexe "c:\Program Files (x86)\Xamarin Studio\bin\XamarinStudio.exe"

Notes for People Preparing Releases

Note the MonoDevelop/Xamarin Studio developers have incorporated the binding into all releases of MonoDevelop and Xamarin Studio. This section remains for reference.

The MonoDevelop Addin mechanism can be hard to easily find information for so here are a couple of links to help get a better understanding.

  • The addin.xml installation schema description can be found here
  • Details about publishing an addin can be found here

The addin used to get released to http://addins.monodevelop.com under project 'FSharp' (project index 48). This is obsolete due to the addin being packaged as part of the Xamarin Studio release cycle. Manual updates can be done although this is only really relevant for linux. Raise an issue for more information or to discuss this.

To build the .mpack files to upload to this site, use:

cd monodevelop
make pack

The pack file goes under pack/...

The build is performed against the installed MonoDevelop or Xamarin Studio on your machine.

For more information about F# see The F# Software Foundation. Join The F# Open Source Group.