fantomas 5.0.0-beta-001

.NET 6.0
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There is a newer version of this package available.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-beta-001
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-beta-001
This package contains a .NET tool you can call from the shell/command line.
#tool dotnet:?package=fantomas&version=5.0.0-beta-001&prerelease
nuke :add-package fantomas --version 5.0.0-beta-001

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 "(%O -> %O)" t1 t2
                 | 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 "(%O -> %O)" t1 t2
             | 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 Versions
.NET net6.0 net6.0-android net6.0-ios net6.0-maccatalyst net6.0-macos net6.0-tvos net6.0-windows
Compatible target framework(s)
Additional computed target framework(s)
Learn more about Target Frameworks and .NET Standard.

This package has no dependencies.

Version Downloads Last updated
5.1.0-alpha-001 85 9/18/2022
5.0.2 109 9/22/2022
5.0.1 471 9/18/2022
5.0.0 1,054 9/16/2022
5.0.0-beta-010 1,689 9/10/2022
5.0.0-beta-009 1,069 9/2/2022
5.0.0-beta-008 1,019 8/30/2022
5.0.0-beta-007 442 8/19/2022
5.0.0-beta-006 1,805 8/12/2022
5.0.0-beta-005 1,672 8/3/2022
5.0.0-beta-004 314 7/27/2022
5.0.0-beta-003 2,271 7/26/2022
5.0.0-beta-002 373 7/19/2022
5.0.0-beta-001 1,814 7/15/2022
5.0.0-alpha-011 440 7/8/2022
5.0.0-alpha-010 1,038 6/27/2022
5.0.0-alpha-009 5,244 6/21/2022
5.0.0-alpha-008 1,130 5/28/2022
5.0.0-alpha-007 594 5/16/2022
5.0.0-alpha-006 664 5/13/2022
5.0.0-alpha-005 168 5/7/2022
5.0.0-alpha-004 387 5/7/2022
5.0.0-alpha-003 593 5/6/2022
5.0.0-alpha-002 79 4/4/2022
5.0.0-alpha-001 69 3/19/2022
4.7.9 3,291 5/2/2022
4.7.8 9,352 4/25/2022
4.7.7 154 4/20/2022
4.7.6 348 4/4/2022
4.7.5 223 3/27/2022
4.7.4 141 3/25/2022
4.7.3 3,742 3/12/2022
4.7.2 126 3/11/2022
4.7.1 130 3/8/2022
4.7.0 223 3/4/2022
4.6.6 139 3/4/2022
4.6.5 823 2/18/2022
4.6.4 195 2/11/2022
4.6.3 198 2/8/2022
4.6.2 262 2/6/2022
4.6.1 230 2/1/2022
4.6.0 672 1/14/2022
4.6.0-beta-001 92 1/8/2022
4.6.0-alpha-011 99 12/29/2021
4.6.0-alpha-010 109 12/4/2021
4.6.0-alpha-009 2,767 11/24/2021
4.6.0-alpha-008 580 11/19/2021
4.6.0-alpha-007 186 11/7/2021
4.6.0-alpha-006 132 11/3/2021
4.6.0-alpha-005 157 10/27/2021
4.6.0-alpha-004 129 10/20/2021
4.6.0-alpha-003 115 10/5/2021
4.6.0-alpha-002 122 9/7/2021
4.6.0-alpha-001 110 8/11/2021
4.5.12 573 1/8/2022
4.5.11 1,403 12/29/2021
4.5.10 1,323 12/4/2021
4.5.9 6,289 11/24/2021
4.5.8 745 11/19/2021
4.5.7 597 11/7/2021
4.5.6 425 11/3/2021
4.5.5 603 10/27/2021
4.5.4 448 10/5/2021
4.5.3 1,997 9/7/2021
4.5.2 555 8/11/2021
4.5.1 1,965 7/24/2021
4.5.0 2,334 7/7/2021
4.5.0-beta-005 247 7/6/2021
4.5.0-beta-004 231 7/5/2021
4.5.0-beta-003 237 7/5/2021
4.5.0-beta-002 250 6/27/2021
4.5.0-beta-001 747 6/5/2021
4.5.0-alpha-020 240 5/26/2021
4.5.0-alpha-019 208 5/22/2021
4.5.0-alpha-018 219 5/21/2021
4.5.0-alpha-017 267 5/15/2021
4.5.0-alpha-016 202 5/9/2021
4.5.0-alpha-015 255 5/8/2021
4.5.0-alpha-014 253 4/30/2021
4.5.0-alpha-013 229 4/27/2021
4.5.0-alpha-012 207 4/23/2021
4.5.0-alpha-011 286 4/20/2021
4.5.0-alpha-010 232 4/14/2021
4.5.0-alpha-009 224 4/11/2021
4.5.0-alpha-008 260 4/8/2021
4.5.0-alpha-007 253 4/8/2021
4.5.0-alpha-006 223 4/5/2021
4.5.0-alpha-005 226 4/3/2021
4.5.0-alpha-004 255 4/2/2021
4.5.0-alpha-003 267 3/28/2021
4.5.0-alpha-002 213 3/22/2021
4.5.0-alpha-001 1,823 2/26/2021
4.4.0 8,980 2/25/2021
4.4.0-beta-008 265 2/19/2021
4.4.0-beta-007 256 2/12/2021
4.4.0-beta-006 257 2/12/2021
4.4.0-beta-005 253 2/9/2021
4.4.0-beta-004 257 2/5/2021
4.4.0-beta-003 693 1/30/2021
4.4.0-beta-002 255 1/23/2021
4.4.0-beta-001 689 1/22/2021
4.4.0-alpha-008 476 1/15/2021
4.4.0-alpha-007 973 12/26/2020
4.4.0-alpha-006 363 12/25/2020
4.4.0-alpha-005 425 12/23/2020
4.4.0-alpha-004 474 12/22/2020
4.4.0-alpha-003 466 12/18/2020
4.4.0-alpha-002 401 12/17/2020
4.4.0-alpha-001 333 12/17/2020
4.3.0 2,752 12/17/2020
4.3.0-beta-002 405 12/11/2020
4.3.0-beta-001 337 12/7/2020
4.3.0-alpha-007 394 11/21/2020
4.3.0-alpha-006 352 11/20/2020
4.3.0-alpha-005 309 11/16/2020
4.3.0-alpha-004 798 11/12/2020
4.3.0-alpha-003 342 11/10/2020
4.3.0-alpha-002 351 10/26/2020
4.3.0-alpha-001 385 10/23/2020
4.2.0 3,858 9/25/2020
4.2.0-alpha-004 543 9/23/2020
4.2.0-alpha-003 358 9/21/2020
4.2.0-alpha-002 397 9/19/2020
4.2.0-alpha-001 466 9/18/2020
4.1.1 710 9/17/2020
4.1.0 941 9/10/2020
4.1.0-beta-004 503 9/5/2020
4.1.0-beta-003 401 9/4/2020
4.1.0-beta-002 811 9/4/2020
4.1.0-beta-001 401 9/3/2020
4.1.0-alpha-001 389 9/1/2020
4.0.0 2,809 8/27/2020
4.0.0-beta-003 418 8/21/2020
4.0.0-beta-002 490 8/7/2020
4.0.0-beta-001 819 7/20/2020
4.0.0-alpha-014 662 7/14/2020
4.0.0-alpha-013 426 7/11/2020
4.0.0-alpha-012 744 7/6/2020
4.0.0-alpha-011 310 6/25/2020
4.0.0-alpha-010 696 6/18/2020
4.0.0-alpha-009 333 6/12/2020
4.0.0-alpha-008 469 6/2/2020
4.0.0-alpha-007 320 6/1/2020
4.0.0-alpha-006 1,157 5/23/2020
4.0.0-alpha-005 1,097 5/16/2020
4.0.0-alpha-004 765 5/4/2020
4.0.0-alpha-003 396 5/3/2020
4.0.0-alpha-002 420 4/26/2020
4.0.0-alpha-001 310 4/20/2020
3.3.0 11,046 2/28/2020
3.3.0-beta-002 1,279 2/21/2020
3.3.0-beta-001 441 2/18/2020
3.2.0 19,960 2/3/2020
3.2.0-beta-002 1,039 1/7/2020
3.2.0-beta-001 583 12/26/2019
3.1.0 9,645 11/27/2019
3.0.0 4,060 10/11/2019
3.0.0-beta-006 1,157 10/2/2019
3.0.0-beta-005 352 9/27/2019
3.0.0-beta-004 950 9/18/2019
3.0.0-beta-003 481 9/13/2019
3.0.0-beta-002 14,072 7/20/2019
3.0.0-beta-001 5,112 7/12/2019
2.9.2 22,861 2/2/2019
2.9.1 3,444 11/20/2018
2.9.0 8,000 10/17/2018
2.8.1 1,496 9/12/2018
2.8.0 4,757 7/7/2018
2.7.1 3,639 5/2/2018
2.7.0 1,236 5/2/2018
2.6.1 44,606 4/22/2017
2.5.0 1,937 2/19/2017
2.4.0 2,041 10/24/2016
2.3.0 1,714 7/9/2016
2.2.0 1,449 4/24/2016
2.1.0 1,319 4/1/2016
2.0.2 8,053 11/15/2015
1.11.0 1,892 9/12/2015
1.10.0 1,248 8/29/2015
1.9.0 1,652 8/10/2015
1.8.0-beta 1,141 7/19/2015
1.7.0 1,398 6/10/2015
1.6.0 2,232 10/25/2014
1.5.0 1,660 9/18/2014
1.4.0 2,014 7/1/2014
1.3.0 1,552 5/17/2014
1.2.0 1,548 4/21/2014
1.1.0 1,419 3/29/2014
1.0.7 1,421 3/12/2014
1.0.5.1 1,479 1/15/2014
1.0.5 1,222 1/7/2014
1.0.4 1,274 11/16/2013
1.0.3 1,297 10/6/2013
1.0.2 1,271 8/16/2013
1.0.1 1,417 7/22/2013
1.0.0 1,705 7/16/2013
0.9.9.2 1,620 7/2/2013
0.9.9.1 1,441 6/22/2013
0.9.8 1,401 6/14/2013
0.9.7 1,372 6/7/2013
0.9.6 1,332 5/31/2013
0.9.5 1,444 5/23/2013
0.9.4 1,336 5/19/2013
0.9.3 1,308 5/9/2013
0.9.2 1,322 5/3/2013
0.9.1 1,599 4/26/2013
0.9.0 1,375 4/19/2013
0.8.9 1,385 4/12/2013
0.8.8 1,323 4/11/2013
0.8.7 1,305 4/9/2013
0.8.6 1,317 4/4/2013
0.8.5 1,388 4/2/2013
0.8.4 1,324 4/1/2013
0.8.3 1,338 4/1/2013
0.8.2 1,303 4/1/2013
0.8.1 1,372 3/31/2013
0.8.0 1,365 3/31/2013

### Changed
* Don't mark optional parameters as required in public API. [#2350](https://github.com/fsprojects/fantomas/pull/2350)
* Update default value for v5. [#2288](https://github.com/fsprojects/fantomas/issues/2288)

### Fixed
* Content of #if block removed - Breaking Code on reformat. [#801](https://github.com/fsprojects/fantomas/issues/801)
* Using a compiler directive copies the previous(?) line in fsi files. [#1186](https://github.com/fsprojects/fantomas/issues/1186)
* Multiline if expression with multiline infix operations. [#1775](https://github.com/fsprojects/fantomas/issues/1775)