fantomas 5.0.0-alpha-004

This is a prerelease version of fantomas.
There is a newer version of this package available.
See the version list below for details.
dotnet tool install --global fantomas --version 5.0.0-alpha-004
This package contains a .NET tool you can call from the shell/command line.
dotnet new tool-manifest # if you are setting up this repo
dotnet tool install --local fantomas --version 5.0.0-alpha-004
This package contains a .NET tool you can call from the shell/command line.
#tool dotnet:?package=fantomas&version=5.0.0-alpha-004&prerelease
nuke :add-package fantomas --version 5.0.0-alpha-004

Fantomas

Fantomas logo

F# source code formatter, inspired by scalariform for Scala, ocp-indent for OCaml and PythonTidy for Python.

Build Status Github Actions Discord

Quick install

How to use

Command line tool / API

Use this command to install Fantomas as a .NET 5 SDK global tool:

dotnet tool install -g fantomas

For detailed guidelines, please read Fantomas: How to use.

FAKE build system

Fantomas can be easily integrated with FAKE build system.<br /> Check out the sample.

JetBrains Rider

The resharper-fsharp uses fantomas under the hood to format the source code. No need for any additional plugins.

Using the latest version inside Rider

For technical reasons Rider cannot always use the latest version of Fantomas found on NuGet. As a workaround you could install fantomas locally with dotnet tool install fantomas-tool and configure it as an External tool.

Rider external tool window

Rider action window

This will have an impact on your editing experiencing in Rider, the external change to the file by the command line application might trigger more internal logic inside Rider than necessary. It could be noticeable in regards to the default formatting experience.

Visual Studio Code

The recommended way to use Fantomas is by using the Ionide plugin. Fantomas is integrated in FSAutoComplete which is the language server used by Ionide.

Alternatively, you can install the fantomas-fmt extension.

Visual Studio

The F# Formatting extension sets up Fantomas as the default formatter for F# files, configurable from Visual Studio's options.

Visual Studio for Mac

Install fantomas locally with dotnet tool install fantomas-tool and configure it as an [External tool]

VS Mac external tool window

Online

Try the Fantomas online.

Early builds

Every once in a while an alpha or beta version is published to https://www.nuget.org/. Our previous MyGet feed is now deprecated.

Benchmarks

Some figures can be found at https://fsprojects.github.io/fantomas/ <br/> We use BenchmarkDotNet to collect data for each build on the master branch.

Purpose

This project aims at formatting F# source files based on a given configuration. Fantomas will ensure correct indentation and consistent spacing between elements in the source files. We assume that the source files are parsable by F# compiler before feeding into the tool. Fantomas follows two F# style guides: the F# code formatting guidelines from Microsoft by default and the G-Research F# code formatting guidelines via various settings.

Use cases

The project is developed with the following use cases in mind:

  • Reformatting an unfamiliar code base. It gives readability when you are not the one originally writing the code. To illustrate, the following example

     type Type
         = TyLam of Type * Type
         | TyVar of string
         | TyCon of string * Type list
         with override this.ToString () =
                 match this with
                 | TyLam (t1, t2) -> sprintf "(%s -> %s)" (t1.ToString()) (t2.ToString())
                 | TyVar a -> a
                 | TyCon (s, ts) -> s
    

    will be rewritten to

     type Type =
         | TyLam of Type * Type
         | TyVar of string
         | TyCon of string * Type list
         override this.ToString() =
             match this with
             | TyLam(t1, t2) -> sprintf "(%s -> %s)" (t1.ToString()) (t2.ToString())
             | TyVar a -> a
             | TyCon(s, ts) -> s
    
  • Converting from verbose syntax to light syntax. Feeding a source file in verbose mode, Fantomas will format it appropriately in light mode. This might be helpful for code generation since generating verbose source files is much easier. For example, this code fragment

     let Multiple9x9 () =
         for i in 1 .. 9 do
             printf "\n";
             for j in 1 .. 9 do
                 let k = i * j in
                 printf "%d x %d = %2d " i j k;
             done;
         done;;
     Multiple9x9 ();;
    

    is reformulated to

     let Multiple9x9() =
         for i in 1..9 do
             printf "\n"
             for j in 1..9 do
                 let k = i * j
                 printf "%d x %d = %2d " i j k
    
     Multiple9x9()
    
  • Formatting F# signatures, especially those generated by F# compiler and F# Interactive.

For more complex examples, please take a look at F# outputs of 20 language shootout programs and 10 CodeReview.SE source files.

Why the name "Fantomas"?

There are a few reasons to choose the name as such. First, it starts with an "F" just like many other F# projects. Second, Fantomas is my favourite character in the literature. Finally, Fantomas has the same Greek root as "phantom"; coincidentally F# ASTs and formatting rules are so mysterious to be handled correctly.

Contributing Guidelines

See the Contribution Guidelines.

Credits

We would like to gratefully thank the following persons for their contributions.

License

The library and tool are available under Apache 2.0 license. For more information see the License file.

Product Compatible and additional computed target framework versions.
.NET net6.0 is compatible.  net6.0-android was computed.  net6.0-ios was computed.  net6.0-maccatalyst was computed.  net6.0-macos was computed.  net6.0-tvos was computed.  net6.0-windows was computed.  net7.0 was computed.  net7.0-android was computed.  net7.0-ios was computed.  net7.0-maccatalyst was computed.  net7.0-macos was computed.  net7.0-tvos was computed.  net7.0-windows was computed.  net8.0 was computed.  net8.0-android was computed.  net8.0-browser was computed.  net8.0-ios was computed.  net8.0-maccatalyst was computed.  net8.0-macos was computed.  net8.0-tvos was computed.  net8.0-windows was computed. 
Compatible target framework(s)
Included target framework(s) (in package)
Learn more about Target Frameworks and .NET Standard.

This package has no dependencies.

Version Downloads Last updated
6.3.0 2,646 3/15/2024
6.3.0-beta-001 479 3/7/2024
6.3.0-alpha-008 611 3/1/2024
6.3.0-alpha-007 1,522 1/27/2024
6.3.0-alpha-006 719 1/9/2024
6.3.0-alpha-005 1,046 12/22/2023
6.3.0-alpha-004 1,618 12/6/2023
6.3.0-alpha-003 1,237 11/15/2023
6.3.0-alpha-002 802 11/7/2023
6.3.0-alpha-001 622 11/3/2023
6.2.3 60,511 11/2/2023
6.2.2 8,170 10/18/2023
6.2.1 8,228 9/18/2023
6.2.0 19,941 8/29/2023
6.1.3 1,296 8/25/2023
6.1.2 11,904 7/23/2023
6.1.1 21,651 6/29/2023
6.1.0 7,408 6/28/2023
6.1.0-alpha-006 1,014 6/20/2023
6.1.0-alpha-005 944 6/20/2023
6.1.0-alpha-004 771 6/19/2023
6.1.0-alpha-003 965 6/2/2023
6.1.0-alpha-002 857 5/2/2023
6.1.0-alpha-001 827 5/2/2023
6.0.8 1,857 6/20/2023
6.0.7 1,119 6/20/2023
6.0.6 1,282 6/19/2023
6.0.5 4,515 6/6/2023
6.0.4 1,246 6/2/2023
6.0.3 11,985 5/14/2023
6.0.2 3,702 5/5/2023
6.0.1 30,621 4/19/2023
6.0.0 21,410 4/13/2023
6.0.0-beta-001 1,375 4/5/2023
6.0.0-alpha-010 4,442 4/3/2023
6.0.0-alpha-009 741 3/31/2023
6.0.0-alpha-008 1,926 3/27/2023
6.0.0-alpha-007 1,189 3/27/2023
6.0.0-alpha-006 1,358 3/17/2023
6.0.0-alpha-005 2,250 2/24/2023
6.0.0-alpha-004 7,794 2/22/2023
6.0.0-alpha-003 2,882 2/4/2023
6.0.0-alpha-002 767 2/1/2023
6.0.0-alpha-001 867 1/24/2023
5.2.4 5,807 3/17/2023
5.2.3 5,282 3/6/2023
5.2.2 11,955 2/21/2023
5.2.1 35,588 2/4/2023
5.2.0 6,624 1/19/2023
5.2.0-alpha-012 1,076 1/14/2023
5.2.0-alpha-011 1,337 1/12/2023
5.2.0-alpha-010 910 12/30/2022
5.2.0-alpha-009 915 12/29/2022
5.2.0-alpha-008 950 12/28/2022
5.2.0-alpha-007 828 12/26/2022
5.2.0-alpha-006 936 12/22/2022
5.2.0-alpha-005 1,021 12/16/2022
5.2.0-alpha-004 1,126 12/8/2022
5.2.0-alpha-003 875 12/6/2022
5.2.0-alpha-002 825 12/4/2022
5.2.0-alpha-001 793 11/30/2022
5.1.5 23,041 12/22/2022
5.1.4 26,286 11/30/2022
5.1.3 6,746 11/14/2022
5.1.2 1,447 11/10/2022
5.1.1 3,940 11/7/2022
5.1.0 2,642 11/4/2022
5.1.0-beta-002 833 10/29/2022
5.1.0-beta-001 1,215 10/19/2022
5.1.0-alpha-007 909 10/14/2022
5.1.0-alpha-006 842 10/14/2022
5.1.0-alpha-005 1,043 10/7/2022
5.1.0-alpha-004 1,046 10/7/2022
5.1.0-alpha-003 1,052 10/2/2022
5.1.0-alpha-002 893 9/29/2022
5.1.0-alpha-001 899 9/18/2022
5.0.6 22,859 10/13/2022
5.0.5 7,953 10/7/2022
5.0.4 1,990 10/4/2022
5.0.3 9,995 9/29/2022
5.0.2 7,577 9/22/2022
5.0.1 4,939 9/18/2022
5.0.0 21,025 9/16/2022
5.0.0-beta-010 16,109 9/10/2022
5.0.0-beta-009 8,617 9/2/2022
5.0.0-beta-008 2,896 8/30/2022
5.0.0-beta-007 1,485 8/19/2022
5.0.0-beta-006 2,737 8/12/2022
5.0.0-beta-005 4,953 8/3/2022
5.0.0-beta-004 2,011 7/27/2022
5.0.0-beta-003 3,572 7/26/2022
5.0.0-beta-002 1,735 7/19/2022
5.0.0-beta-001 2,741 7/15/2022
5.0.0-alpha-011 1,451 7/8/2022
5.0.0-alpha-010 2,044 6/27/2022
5.0.0-alpha-009 63,032 6/21/2022
5.0.0-alpha-008 2,685 5/28/2022
5.0.0-alpha-007 1,659 5/16/2022
5.0.0-alpha-006 1,709 5/13/2022
5.0.0-alpha-005 1,216 5/7/2022
5.0.0-alpha-004 1,283 5/7/2022
5.0.0-alpha-003 1,737 5/6/2022
5.0.0-alpha-002 668 4/4/2022
5.0.0-alpha-001 628 3/19/2022
4.7.9 10,818 5/2/2022
4.7.8 10,471 4/25/2022
4.7.7 1,101 4/20/2022
4.7.6 1,371 4/4/2022
4.7.5 1,218 3/27/2022
4.7.4 1,189 3/25/2022
4.7.3 4,762 3/12/2022
4.7.2 1,095 3/11/2022
4.7.1 1,074 3/8/2022
4.7.0 1,245 3/4/2022
4.6.6 1,134 3/4/2022
4.6.5 1,861 2/18/2022
4.6.4 1,614 2/11/2022
4.6.3 1,679 2/8/2022
4.6.2 1,683 2/6/2022
4.6.1 1,654 2/1/2022
4.6.0 2,170 1/14/2022
4.6.0-beta-001 736 1/8/2022
4.6.0-alpha-011 712 12/29/2021
4.6.0-alpha-010 718 12/4/2021
4.6.0-alpha-009 3,377 11/24/2021
4.6.0-alpha-008 1,163 11/19/2021
4.6.0-alpha-007 781 11/7/2021
4.6.0-alpha-006 194 11/3/2021
4.6.0-alpha-005 219 10/27/2021
4.6.0-alpha-004 198 10/20/2021
4.6.0-alpha-003 178 10/5/2021
4.6.0-alpha-002 190 9/7/2021
4.6.0-alpha-001 166 8/11/2021
4.5.12 1,539 1/8/2022
4.5.11 2,304 12/29/2021
4.5.10 2,584 12/4/2021
4.5.9 7,461 11/24/2021
4.5.8 1,678 11/19/2021
4.5.7 1,507 11/7/2021
4.5.6 1,296 11/3/2021
4.5.5 1,458 10/27/2021
4.5.4 1,366 10/5/2021
4.5.3 2,867 9/7/2021
4.5.2 1,509 8/11/2021
4.5.1 3,322 7/24/2021
4.5.0 3,278 7/7/2021
4.5.0-beta-005 829 7/6/2021
4.5.0-beta-004 819 7/5/2021
4.5.0-beta-003 851 7/5/2021
4.5.0-beta-002 844 6/27/2021
4.5.0-beta-001 1,337 6/5/2021
4.5.0-alpha-020 809 5/26/2021
4.5.0-alpha-019 794 5/22/2021
4.5.0-alpha-018 827 5/21/2021
4.5.0-alpha-017 814 5/15/2021
4.5.0-alpha-016 767 5/9/2021
4.5.0-alpha-015 876 5/8/2021
4.5.0-alpha-014 887 4/30/2021
4.5.0-alpha-013 841 4/27/2021
4.5.0-alpha-012 799 4/23/2021
4.5.0-alpha-011 909 4/20/2021
4.5.0-alpha-010 823 4/14/2021
4.5.0-alpha-009 833 4/11/2021
4.5.0-alpha-008 835 4/8/2021
4.5.0-alpha-007 852 4/8/2021
4.5.0-alpha-006 803 4/5/2021
4.5.0-alpha-005 817 4/3/2021
4.5.0-alpha-004 850 4/2/2021
4.5.0-alpha-003 865 3/28/2021
4.5.0-alpha-002 857 3/22/2021
4.5.0-alpha-001 2,478 2/26/2021
4.4.0 12,890 2/25/2021
4.4.0-beta-008 881 2/19/2021
4.4.0-beta-007 894 2/12/2021
4.4.0-beta-006 886 2/12/2021
4.4.0-beta-005 944 2/9/2021
4.4.0-beta-004 919 2/5/2021
4.4.0-beta-003 1,366 1/30/2021
4.4.0-beta-002 912 1/23/2021
4.4.0-beta-001 1,315 1/22/2021
4.4.0-alpha-008 1,100 1/15/2021
4.4.0-alpha-007 1,582 12/26/2020
4.4.0-alpha-006 993 12/25/2020
4.4.0-alpha-005 1,077 12/23/2020
4.4.0-alpha-004 1,091 12/22/2020
4.4.0-alpha-003 1,112 12/18/2020
4.4.0-alpha-002 1,086 12/17/2020
4.4.0-alpha-001 981 12/17/2020
4.3.0 5,493 12/17/2020
4.3.0-beta-002 1,035 12/11/2020
4.3.0-beta-001 981 12/7/2020
4.3.0-alpha-007 1,011 11/21/2020
4.3.0-alpha-006 1,006 11/20/2020
4.3.0-alpha-005 956 11/16/2020
4.3.0-alpha-004 1,467 11/12/2020
4.3.0-alpha-003 1,036 11/10/2020
4.3.0-alpha-002 1,015 10/26/2020
4.3.0-alpha-001 1,044 10/23/2020
4.2.0 4,865 9/25/2020
4.2.0-alpha-004 1,180 9/23/2020
4.2.0-alpha-003 987 9/21/2020
4.2.0-alpha-002 1,070 9/19/2020
4.2.0-alpha-001 1,106 9/18/2020
4.1.1 1,680 9/17/2020
4.1.0 1,901 9/10/2020
4.1.0-beta-004 1,143 9/5/2020
4.1.0-beta-003 1,071 9/4/2020
4.1.0-beta-002 1,439 9/4/2020
4.1.0-beta-001 1,031 9/3/2020
4.1.0-alpha-001 1,036 9/1/2020
4.0.0 4,021 8/27/2020
4.0.0-beta-003 1,064 8/21/2020
4.0.0-beta-002 1,148 8/7/2020
4.0.0-beta-001 1,467 7/20/2020
4.0.0-alpha-014 1,278 7/14/2020
4.0.0-alpha-013 1,075 7/11/2020
4.0.0-alpha-012 1,834 7/6/2020
4.0.0-alpha-011 934 6/25/2020
4.0.0-alpha-010 1,309 6/18/2020
4.0.0-alpha-009 971 6/12/2020
4.0.0-alpha-008 1,104 6/2/2020
4.0.0-alpha-007 981 6/1/2020
4.0.0-alpha-006 2,192 5/23/2020
4.0.0-alpha-005 2,008 5/16/2020
4.0.0-alpha-004 1,397 5/4/2020
4.0.0-alpha-003 1,042 5/3/2020
4.0.0-alpha-002 1,089 4/26/2020
4.0.0-alpha-001 985 4/20/2020
3.3.0 12,711 2/28/2020
3.3.0-beta-002 1,923 2/21/2020
3.3.0-beta-001 1,098 2/18/2020
3.2.0 21,096 2/3/2020
3.2.0-beta-002 1,666 1/7/2020
3.2.0-beta-001 1,227 12/26/2019
3.1.0 10,597 11/27/2019
3.0.0 4,948 10/11/2019
3.0.0-beta-006 1,805 10/2/2019
3.0.0-beta-005 992 9/27/2019
3.0.0-beta-004 1,568 9/18/2019
3.0.0-beta-003 1,114 9/13/2019
3.0.0-beta-002 16,187 7/20/2019
3.0.0-beta-001 5,780 7/12/2019
2.9.2 25,478 2/2/2019
2.9.1 4,885 11/20/2018
2.9.0 11,130 10/17/2018
2.8.1 2,691 9/12/2018
2.8.0 5,908 7/7/2018
2.7.1 4,790 5/2/2018
2.7.0 2,437 5/2/2018
2.6.1 45,619 4/22/2017
2.5.0 2,879 2/19/2017
2.4.0 2,980 10/24/2016
2.3.0 2,649 7/9/2016
2.2.0 2,394 4/24/2016
2.1.0 2,286 4/1/2016
2.0.2 9,024 11/15/2015
1.11.0 2,820 9/12/2015
1.10.0 2,176 8/29/2015
1.9.0 2,623 8/10/2015
1.8.0-beta 1,808 7/19/2015
1.7.0 2,277 6/10/2015
1.6.0 3,156 10/25/2014
1.5.0 2,614 9/18/2014
1.4.0 2,989 7/1/2014
1.3.0 2,478 5/17/2014
1.2.0 2,489 4/21/2014
1.1.0 2,398 3/29/2014
1.0.7 2,356 3/12/2014
1.0.5.1 2,454 1/15/2014
1.0.5 2,185 1/7/2014
1.0.4 2,269 11/16/2013
1.0.3 2,286 10/6/2013
1.0.2 2,226 8/16/2013
1.0.1 2,414 7/22/2013
1.0.0 5,302 7/16/2013
0.9.9.2 2,622 7/2/2013
0.9.9.1 2,392 6/22/2013
0.9.8 2,393 6/14/2013
0.9.7 2,329 6/7/2013
0.9.6 2,321 5/31/2013
0.9.5 2,408 5/23/2013
0.9.4 2,259 5/19/2013
0.9.3 2,290 5/9/2013
0.9.2 2,302 5/3/2013
0.9.1 2,521 4/26/2013
0.9.0 2,305 4/19/2013
0.8.9 2,367 4/12/2013
0.8.8 2,335 4/11/2013
0.8.7 2,252 4/9/2013
0.8.6 2,268 4/4/2013
0.8.5 2,353 4/2/2013
0.8.4 2,268 4/1/2013
0.8.3 2,343 4/1/2013
0.8.2 2,248 4/1/2013
0.8.1 2,413 3/31/2013
0.8.0 2,337 3/31/2013

### Changed
* FCS: Expose FSharpParserDiagnostic from parseFile. [https://github.com/fsprojects/fantomas/pull/2233](2233)