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There is a newer version of this package available.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
7.0.0-alpha-002 71 11/2/2024
7.0.0-alpha-001 114 9/16/2024
6.3.16 2,086 10/29/2024
6.3.15 13,272 9/14/2024
6.3.14 111 9/14/2024
6.3.13 865 9/10/2024
6.3.12 3,903 9/5/2024
6.3.11 14,547 8/16/2024
6.3.10 15,932 7/12/2024
6.3.9 18,943 6/9/2024
6.3.8 945 6/6/2024
6.3.7 1,714 6/1/2024
6.3.6 178 6/1/2024
6.3.5 851 5/30/2024
6.3.4 23,906 4/16/2024
6.3.3 4,420 4/12/2024
6.3.2 296 4/12/2024
6.3.1 10,832 3/30/2024
6.3.0 13,755 3/15/2024
6.3.0-beta-001 1,040 3/7/2024
6.3.0-alpha-008 813 3/1/2024
6.3.0-alpha-007 1,949 1/27/2024
6.3.0-alpha-006 831 1/9/2024
6.3.0-alpha-005 1,210 12/22/2023
6.3.0-alpha-004 1,903 12/6/2023
6.3.0-alpha-003 1,468 11/15/2023
6.3.0-alpha-002 924 11/7/2023
6.3.0-alpha-001 770 11/3/2023
6.2.3 116,816 11/2/2023
6.2.2 26,387 10/18/2023
6.2.1 9,698 9/18/2023
6.2.0 24,399 8/29/2023
6.1.3 1,442 8/25/2023
6.1.2 14,588 7/23/2023
6.1.1 76,521 6/29/2023
6.1.0 7,533 6/28/2023
6.1.0-alpha-006 1,103 6/20/2023
6.1.0-alpha-005 1,028 6/20/2023
6.1.0-alpha-004 843 6/19/2023
6.1.0-alpha-003 1,111 6/2/2023
6.1.0-alpha-002 974 5/2/2023
6.1.0-alpha-001 982 5/2/2023
6.0.8 1,980 6/20/2023
6.0.7 1,276 6/20/2023
6.0.6 1,461 6/19/2023
6.0.5 4,948 6/6/2023
6.0.4 1,307 6/2/2023
6.0.3 12,438 5/14/2023
6.0.2 4,149 5/5/2023
6.0.1 61,502 4/19/2023
6.0.0 42,749 4/13/2023
6.0.0-beta-001 1,485 4/5/2023
6.0.0-alpha-010 7,053 4/3/2023
6.0.0-alpha-009 818 3/31/2023
6.0.0-alpha-008 2,064 3/27/2023
6.0.0-alpha-007 1,349 3/27/2023
6.0.0-alpha-006 1,488 3/17/2023
6.0.0-alpha-005 2,366 2/24/2023
6.0.0-alpha-004 8,941 2/22/2023
6.0.0-alpha-003 2,946 2/4/2023
6.0.0-alpha-002 893 2/1/2023
6.0.0-alpha-001 1,032 1/24/2023
5.2.4 6,109 3/17/2023
5.2.3 5,515 3/6/2023
5.2.2 13,225 2/21/2023
5.2.1 59,552 2/4/2023
5.2.0 6,837 1/19/2023
5.2.0-alpha-012 1,164 1/14/2023
5.2.0-alpha-011 1,383 1/12/2023
5.2.0-alpha-010 1,088 12/30/2022
5.2.0-alpha-009 1,022 12/29/2022
5.2.0-alpha-008 1,240 12/28/2022
5.2.0-alpha-007 1,012 12/26/2022
5.2.0-alpha-006 1,017 12/22/2022
5.2.0-alpha-005 1,146 12/16/2022
5.2.0-alpha-004 1,259 12/8/2022
5.2.0-alpha-003 1,030 12/6/2022
5.2.0-alpha-002 985 12/4/2022
5.2.0-alpha-001 925 11/30/2022
5.1.5 25,215 12/22/2022
5.1.4 26,803 11/30/2022
5.1.3 7,474 11/14/2022
5.1.2 1,540 11/10/2022
5.1.1 4,067 11/7/2022
5.1.0 2,758 11/4/2022
5.1.0-beta-002 993 10/29/2022
5.1.0-beta-001 1,363 10/19/2022
5.1.0-alpha-007 1,040 10/14/2022
5.1.0-alpha-006 997 10/14/2022
5.1.0-alpha-005 1,140 10/7/2022
5.1.0-alpha-004 1,153 10/7/2022
5.1.0-alpha-003 1,163 10/2/2022
5.1.0-alpha-002 1,047 9/29/2022
5.1.0-alpha-001 1,088 9/18/2022
5.0.6 24,688 10/13/2022
5.0.5 9,964 10/7/2022
5.0.4 2,181 10/4/2022
5.0.3 10,675 9/29/2022
5.0.2 8,247 9/22/2022
5.0.1 6,359 9/18/2022
5.0.0 21,221 9/16/2022
5.0.0-beta-010 21,454 9/10/2022
5.0.0-beta-009 9,472 9/2/2022
5.0.0-beta-008 3,023 8/30/2022
5.0.0-beta-007 1,606 8/19/2022
5.0.0-beta-006 2,920 8/12/2022
5.0.0-beta-005 5,076 8/3/2022
5.0.0-beta-004 2,293 7/27/2022
5.0.0-beta-003 3,709 7/26/2022
5.0.0-beta-002 1,895 7/19/2022
5.0.0-beta-001 2,888 7/15/2022
5.0.0-alpha-011 1,612 7/8/2022
5.0.0-alpha-010 2,187 6/27/2022
5.0.0-alpha-009 78,268 6/21/2022
5.0.0-alpha-008 3,018 5/28/2022
5.0.0-alpha-007 1,839 5/16/2022
5.0.0-alpha-006 1,861 5/13/2022
5.0.0-alpha-005 1,343 5/7/2022
5.0.0-alpha-004 1,435 5/7/2022
5.0.0-alpha-003 1,892 5/6/2022
5.0.0-alpha-002 741 4/4/2022
5.0.0-alpha-001 691 3/19/2022
4.7.9 11,171 5/2/2022
4.7.8 10,539 4/25/2022
4.7.7 1,161 4/20/2022
4.7.6 1,432 4/4/2022
4.7.5 1,285 3/27/2022
4.7.4 1,249 3/25/2022
4.7.3 4,819 3/12/2022
4.7.2 1,173 3/11/2022
4.7.1 1,139 3/8/2022
4.7.0 1,292 3/4/2022
4.6.6 1,198 3/4/2022
4.6.5 1,953 2/18/2022
4.6.4 1,718 2/11/2022
4.6.3 1,767 2/8/2022
4.6.2 1,754 2/6/2022
4.6.1 1,748 2/1/2022
4.6.0 2,251 1/14/2022
4.6.0-beta-001 812 1/8/2022
4.6.0-alpha-011 795 12/29/2021
4.6.0-alpha-010 809 12/4/2021
4.6.0-alpha-009 3,449 11/24/2021
4.6.0-alpha-008 1,225 11/19/2021
4.6.0-alpha-007 848 11/7/2021
4.6.0-alpha-006 205 11/3/2021
4.6.0-alpha-005 229 10/27/2021
4.6.0-alpha-004 207 10/20/2021
4.6.0-alpha-003 188 10/5/2021
4.6.0-alpha-002 200 9/7/2021
4.6.0-alpha-001 176 8/11/2021
4.5.12 1,616 1/8/2022
4.5.11 2,404 12/29/2021
4.5.10 2,648 12/4/2021
4.5.9 7,541 11/24/2021
4.5.8 1,755 11/19/2021
4.5.7 1,579 11/7/2021
4.5.6 1,377 11/3/2021
4.5.5 1,534 10/27/2021
4.5.4 1,440 10/5/2021
4.5.3 2,942 9/7/2021
4.5.2 1,588 8/11/2021
4.5.1 3,436 7/24/2021
4.5.0 3,357 7/7/2021
4.5.0-beta-005 916 7/6/2021
4.5.0-beta-004 891 7/5/2021
4.5.0-beta-003 921 7/5/2021
4.5.0-beta-002 920 6/27/2021
4.5.0-beta-001 1,415 6/5/2021
4.5.0-alpha-020 865 5/26/2021
4.5.0-alpha-019 877 5/22/2021
4.5.0-alpha-018 912 5/21/2021
4.5.0-alpha-017 870 5/15/2021
4.5.0-alpha-016 841 5/9/2021
4.5.0-alpha-015 932 5/8/2021
4.5.0-alpha-014 979 4/30/2021
4.5.0-alpha-013 897 4/27/2021
4.5.0-alpha-012 887 4/23/2021
4.5.0-alpha-011 981 4/20/2021
4.5.0-alpha-010 897 4/14/2021
4.5.0-alpha-009 907 4/11/2021
4.5.0-alpha-008 906 4/8/2021
4.5.0-alpha-007 927 4/8/2021
4.5.0-alpha-006 880 4/5/2021
4.5.0-alpha-005 907 4/3/2021
4.5.0-alpha-004 923 4/2/2021
4.5.0-alpha-003 969 3/28/2021
4.5.0-alpha-002 936 3/22/2021
4.5.0-alpha-001 2,562 2/26/2021
4.4.0 13,322 2/25/2021
4.4.0-beta-008 977 2/19/2021
4.4.0-beta-007 968 2/12/2021
4.4.0-beta-006 957 2/12/2021
4.4.0-beta-005 1,016 2/9/2021
4.4.0-beta-004 1,001 2/5/2021
4.4.0-beta-003 1,455 1/30/2021
4.4.0-beta-002 987 1/23/2021
4.4.0-beta-001 1,390 1/22/2021
4.4.0-alpha-008 1,157 1/15/2021
4.4.0-alpha-007 1,656 12/26/2020
4.4.0-alpha-006 1,068 12/25/2020
4.4.0-alpha-005 1,152 12/23/2020
4.4.0-alpha-004 1,176 12/22/2020
4.4.0-alpha-003 1,187 12/18/2020
4.4.0-alpha-002 1,157 12/17/2020
4.4.0-alpha-001 1,056 12/17/2020
4.3.0 5,628 12/17/2020
4.3.0-beta-002 1,112 12/11/2020
4.3.0-beta-001 1,072 12/7/2020
4.3.0-alpha-007 1,086 11/21/2020
4.3.0-alpha-006 1,081 11/20/2020
4.3.0-alpha-005 1,031 11/16/2020
4.3.0-alpha-004 1,522 11/12/2020
4.3.0-alpha-003 1,110 11/10/2020
4.3.0-alpha-002 1,090 10/26/2020
4.3.0-alpha-001 1,119 10/23/2020
4.2.0 4,980 9/25/2020
4.2.0-alpha-004 1,270 9/23/2020
4.2.0-alpha-003 1,068 9/21/2020
4.2.0-alpha-002 1,137 9/19/2020
4.2.0-alpha-001 1,187 9/18/2020
4.1.1 1,764 9/17/2020
4.1.0 1,978 9/10/2020
4.1.0-beta-004 1,217 9/5/2020
4.1.0-beta-003 1,155 9/4/2020
4.1.0-beta-002 1,507 9/4/2020
4.1.0-beta-001 1,129 9/3/2020
4.1.0-alpha-001 1,111 9/1/2020
4.0.0 4,161 8/27/2020
4.0.0-beta-003 1,159 8/21/2020
4.0.0-beta-002 1,207 8/7/2020
4.0.0-beta-001 1,527 7/20/2020
4.0.0-alpha-014 1,336 7/14/2020
4.0.0-alpha-013 1,144 7/11/2020
4.0.0-alpha-012 1,971 7/6/2020
4.0.0-alpha-011 994 6/25/2020
4.0.0-alpha-010 1,370 6/18/2020
4.0.0-alpha-009 1,048 6/12/2020
4.0.0-alpha-008 1,169 6/2/2020
4.0.0-alpha-007 1,041 6/1/2020
4.0.0-alpha-006 2,312 5/23/2020
4.0.0-alpha-005 2,143 5/16/2020
4.0.0-alpha-004 1,455 5/4/2020
4.0.0-alpha-003 1,107 5/3/2020
4.0.0-alpha-002 1,147 4/26/2020
4.0.0-alpha-001 1,045 4/20/2020
3.3.0 12,897 2/28/2020
3.3.0-beta-002 1,984 2/21/2020
3.3.0-beta-001 1,158 2/18/2020
3.2.0 21,186 2/3/2020
3.2.0-beta-002 1,727 1/7/2020
3.2.0-beta-001 1,287 12/26/2019
3.1.0 10,663 11/27/2019
3.0.0 5,013 10/11/2019
3.0.0-beta-006 1,868 10/2/2019
3.0.0-beta-005 1,052 9/27/2019
3.0.0-beta-004 1,629 9/18/2019
3.0.0-beta-003 1,189 9/13/2019
3.0.0-beta-002 16,602 7/20/2019
3.0.0-beta-001 5,866 7/12/2019
2.9.2 25,736 2/2/2019
2.9.1 4,963 11/20/2018
2.9.0 11,375 10/17/2018
2.8.1 2,783 9/12/2018
2.8.0 5,986 7/7/2018
2.7.1 4,869 5/2/2018
2.7.0 2,520 5/2/2018
2.6.1 45,696 4/22/2017
2.5.0 2,946 2/19/2017
2.4.0 3,065 10/24/2016
2.3.0 2,720 7/9/2016
2.2.0 2,458 4/24/2016
2.1.0 2,352 4/1/2016
2.0.2 9,089 11/15/2015
1.11.0 2,888 9/12/2015
1.10.0 2,242 8/29/2015
1.9.0 2,698 8/10/2015
1.8.0-beta 1,874 7/19/2015
1.7.0 2,353 6/10/2015
1.6.0 3,221 10/25/2014
1.5.0 2,687 9/18/2014
1.4.0 3,054 7/1/2014
1.3.0 2,547 5/17/2014
1.2.0 2,560 4/21/2014
1.1.0 2,480 3/29/2014
1.0.7 2,434 3/12/2014
1.0.5.1 2,532 1/15/2014
1.0.5 2,255 1/7/2014
1.0.4 2,340 11/16/2013
1.0.3 2,355 10/6/2013
1.0.2 2,296 8/16/2013
1.0.1 2,486 7/22/2013
1.0.0 5,580 7/16/2013
0.9.9.2 2,692 7/2/2013
0.9.9.1 2,463 6/22/2013
0.9.8 2,451 6/14/2013
0.9.7 2,404 6/7/2013
0.9.6 2,388 5/31/2013
0.9.5 2,475 5/23/2013
0.9.4 2,327 5/19/2013
0.9.3 2,355 5/9/2013
0.9.2 2,376 5/3/2013
0.9.1 2,590 4/26/2013
0.9.0 2,373 4/19/2013
0.8.9 2,437 4/12/2013
0.8.8 2,402 4/11/2013
0.8.7 2,318 4/9/2013
0.8.6 2,337 4/4/2013
0.8.5 2,420 4/2/2013
0.8.4 2,346 4/1/2013
0.8.3 2,413 4/1/2013
0.8.2 2,297 4/1/2013
0.8.1 2,482 3/31/2013
0.8.0 2,422 3/31/2013

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