Fesh 0.14.1
dotnet add package Fesh --version 0.14.1
NuGet\Install-Package Fesh -Version 0.14.1
<PackageReference Include="Fesh" Version="0.14.1" />
paket add Fesh --version 0.14.1
#r "nuget: Fesh, 0.14.1"
// Install Fesh as a Cake Addin #addin nuget:?package=Fesh&version=0.14.1 // Install Fesh as a Cake Tool #tool nuget:?package=Fesh&version=0.14.1
Fesh
Fesh is an F# Editor & Scripting Host.
On Windows.
It is designed for embedding F# as application scripting tool.
But it works standalone just as well.
It is based on the excellent AvalonEdit, that is why it only works on Windows (for now).
The editor supports F# 8.0 and has modern IDE features like semantic syntax highlighting, type-info and autocomplete.
Unlike a typical F# REPL this editor has the input and the output in two separate windows.
Just like Don Syme always wanted it.
You can even color the output with Fescher.
Contrary to most F# editors, it uses FSharp.Compiler.Service in the same process as the UI.
There is no separate language server or FSI process.
Therefore, Fesh can easily be hosted in other apps to create an embedded application scripting tool.
This was in fact the primary motivation for creating Fesh.
It is public since 2024.
But I started prototyping it in 2017. I used it for scripting in Rhino3D professionally since 2019.
Initially I used the Tsunami F# editor, like seen in my talk on the Louvre Abu Dhabi Dome.
But it is no longer available. So I created Fesh.
For hosting there is the nuget package Fesh. See hosting examples Fesh.Rhino and Fesh.Revit.
How to install
Standalone
Build from the source with
dotnet build FeshStandalone.fsproj
or download the from Releases to any location, unblock and run Fesh.exe.
For hosting in another app
use the nuget package Fesh.
Or, to build the Fesh nuget package run:
dotnet build FeshHosting.fsproj
Features
Syntax Highlighting
Initial static syntax highlighting is done via AvalonEdit's regex based highlighting.
See SyntaxHighlightingFSharp.xshd.
The F# Compiler Service provides additional semantic highlighting.
If you want different colors go the menu: About
→ Open and watch SyntaxHighlighting in VS Code
.
You wil see any changes upon every save in VS Code.
Auto complete
Auto complete works on enter and dot, also when typing in the middle of a word.
Type info
The type info includes the inferred signature.
All of the xml docs and information about the path of the containing assembly.
Status bar
The statusbar at the bottom shows compiler error count, click on it to scroll to the first error.
Selection highlighting
Selected text is highlighted in both code and output window. The count is shown in the status bar.
Drag and drop
Drag any file or folder into the editor to get the full path as a string at the cursor position.
For *.dlls it will be at the top and prefixed with #r
.
For *.fsx it will be at the top and prefixed with #load
.
Font
The default font is Cascadia Mono.
You can change it in the 'Settings.txt' file at %APPDATA%\Local\Fesh\Settings.txt
.
Or via the menu: About
→ Open Settings Folder
.
Release notes
0.14.0
- fix bug in unsaved settings
0.13.0
- fix crash on assembly load conflict
- faster completion window
- optional tracking of evaluated code via settings
0.12.0
- add check for updates on startup
- fix version number in Title
- enable cancellation of running code in net48 and net8
0.11.1
- fix expiry date
0.11.0
- fix VisualLine not collapsed crash
0.10.0
- enable DefaultCode in host settings
0.9.0
- first public release
Product | Versions Compatible and additional computed target framework versions. |
---|---|
.NET | net7.0-windows7.0 is compatible. net8.0-windows was computed. |
.NET Framework | net472 is compatible. net48 was computed. net481 was computed. |
-
.NETFramework 4.7.2
- AvalonLog (>= 0.16.0)
- Fittings (>= 0.8.8)
- FSharp.Compiler.Service (>= 43.8.400)
- FSharp.Core (>= 8.0.400)
- System.Net.Http (>= 4.3.4)
-
net7.0-windows7.0
- AvalonLog (>= 0.16.0)
- Fittings (>= 0.8.8)
- FSharp.Compiler.Service (>= 43.8.400)
- FSharp.Core (>= 8.0.400)
- System.Net.Http (>= 4.3.4)
NuGet packages
This package is not used by any NuGet packages.
GitHub repositories
This package is not used by any popular GitHub repositories.
- add FSI.Shutdown command for hosting