**Before we start, are sure you're in the right place?**

* To get a free F# environment for Windows, go to[fsharp.net](http://fsharp.net).

* To get a free F# environment for Linux or Mac, go to[fsxplat.codeplex.com](http://fsxplat.codeplex.com).

* To learn what F# is and why it's interesting, go to[fsharp.net](http://fsharp.net) or[tryfsharp.org](http://tryfsharp.org).

* If you want to to use F# in Visual Studio 2010 (R) or Visual Studio 2012 (R), go to[fsharp.net](http://fsharp.net).

* Looking for F# coding samples? Go to[fsharp.net](http://fsharp.net) or[tryfsharp.org](http://tryfsharp.org) or[fssnip.net](http://fssnip.net). While the code has its nice points, it is not a model F# codebase and should not be used as guidance for F# coding style - there are plenty of things we would change if we had all the time in the world.

To emphasize, this distribution should not be seen as a way to "get" an F# compiler for immediate use. For that you're better going to[fsharp.net](http://fsharp.net) or[fsxplat.codeplex.com](http://fsxplat.codeplex.com)

**License:** subject to terms and conditions of the Apache License, Version 2.0. A copy of the license can be found in the License.html file at the root of this distribution. By using this source code in any fashion, you are agreeing to be bound by the terms of the Apache License, Version 2.0. You must not remove this notice, or any other, from this software.

**Questions?** If you have questions about the source code, please ask at the[F# Open Source Google Group](http://groups.google.com/group/fsharp-opensource). Please do not ask the F# team at Microsoft for help with this source code: they like to be friendly, but they are very busy working on improving F# and need to focus on that.

**Copyright:** Copyright 2002-2012 (c) Microsoft Corporation.

##What do I get when I compile?

When you build the compiler using the standard instructions below, you get`fsc.exe`,`fsi.exe`,`FSharp.Core.dll`,`FSharp.Compiler.dll` and some related DLLs.

The compiler binaries produced are "private" and strong-named signed with a test key (`src\fsharp\test.snk`). They use CLI assembly version nunmber**2.9.9.999**. You can place these components in the GAC but they will not replace the components used by normal Visual Studio or normal F# programs.

##Building Everything

##Building Everything for .NET 2.0 and 4.0 with msbuild/build

To just build everything use:

##Step by step - Building a Proto Compiler

If you prefer to do things the slow way, then this is step 1:

Note: Make sure you run the .NET 4.0`msbuild.exe`, e.g.`C:\Windows\Microsoft.NET\Framework\v4.0.30319\MSBuild.exe`.

Note: On Windows, make sure you run the .NET 4.0`msbuild.exe`, e.g.`C:\Windows\Microsoft.NET\Framework\v4.0.30319\MSBuild.exe`.

On Linux and Mac, you can use xbuild.

Optional: NGEN the Proto Compiler for faster future startup (optional)

##Steps - Building the F# Core Library

##Steps - Building the F# Core Library with msbuild/build

This uses the proto compiler to build the FSharp.Core library, for Mono/.NET 4.0.

The next step uses the proto compiler to build the FSharp.Core library, for Mono/.NET 4.0.

Note: Make sure you run the .NET 4.0`msbuild.exe`, e.g.`C:\Windows\Microsoft.NET\Framework\v4.0.30319\MSBuild.exe`.

##Steps - Building the F# Compiler

##Steps - Building the F# Compiler with msbuild/build

This uses the proto compiler to build the`FSharp.Compiler.dll` and`fsc.exe` to run on for Mono/.NET 4.0.

The next step uses the proto compiler to build the`FSharp.Compiler.dll` and`fsc.exe` to run on for Mono/.NET 4.0.

Note: Make sure you run the .NET 4.0`msbuild.exe`, e.g.`C:\Windows\Microsoft.NET\Framework\v4.0.30319\MSBuild.exe`.

##Steps -Buildinga compiler componentforhosting in the browserwithSilverlight or Moonlight

##Buildingthe F# core libraryforalternative CLI/.NET/CIL implementationswithmsbuild/build

This builds`FSharp.Compiler.Silverlight.dll` which is a Silverlight 5.0 component for hosting in the browser.

*Debug configuration for browser-hosted compiler for Silverlight 5.0:*

*Release configuration for browser-hosted compiler for Silverlight 5.0:*

The binaries are placed in`Debug\sl5-compiler`,`Release\sl5-compiler`,`Debug\sl5-compiler` and/or`Release\sl5-compiler`. A custom`FSharp.Core.dll` is used for this configuration, be sure to reference it rather than any other`FSharp.Core.dll` for Silverlight. You may have to edit your project file by hand to ensure you get exactly the right reference to`FSharp.Core.dll`.

Here**net20** gives a runtime for .NET 2.0-3.5,**mono21** fives a runtime for MonoAnrdoid and MonoTouch,

**sl3-wp** gives a runtime for Windows Phone 7, and**sl5** gives a runtime for Silverlight 5.

To build these libraries you may need the corresponding tools installed (e.g. MonoAndroid or the Silverlight tools)

##Building the F# core library for alternative CLI/.NET/CIL implementations

##Some alternative Steps - Building an optimized (Release) compiler and libraries

Here**net20** gives a runtime for .NET 2.0-3.5,**sl3-wp** gives a runtime for Windows Phone 7, and**sl5** gives a runtime for Silverlight 5.

##Steps - Building F# Core Unit Tests for .NET 4.x (optional)

This uses the proto compiler to build the unit tests that check some parts of`FSharp.Core.dll` and`FSharp.Compiler.dll`. There is also another set of tests under`tests\fsharp`.

The results file will contain one entry for each test directory, plus any reported errors.

Some tests for LINQ queries require SQL Server be installed. A failing test will look like this:

You can then go to the relevant directory and run`build.bat` and`run.bat`.

However, this is not recommended except in the rare case you are adding extra functionality to`FSharp.Core` - it is better to just continue to run with the`FSharp.Core` that comes with Visual Studio 2012.

##Preparing for inclusion in Mono

Building for the**mono20** and**mono40** frameworks gives strong-named, delay-signed assemblies with the`msfinal.pub` key and standard version numbers such as**2.0.0.0**,**2.3.0.0**,**4.0.0.0** and**4.3.0.0**. You complete the signing of these assemblies using[http://github.com/fsharp/fsharp/raw/master/mono.snk](http://github.com/fsharp/fsharp/raw/master/mono.snk). These assemblies will not run if you already have a version of them installed in your GAC (e.g. if you have Visual Studio 2012).

##Some alternative Steps - Building for .NET 2.0 profile

##Some alternative Steps - Building an optimized (Release) compiler for .NET 4.0 profile

##Some alternative Steps - Other examples of building for Release mode (choose some of these as you need)

##Editing and Building on Windows using Visual Studio 2012

###Prerequisites