fantomas 8.0.0-alpha-014

This is a prerelease version of fantomas.
There is a newer prerelease version of this package available.
See the version list below for details.
dotnet tool install --global fantomas --version 8.0.0-alpha-014
                    
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 8.0.0-alpha-014
                    
This package contains a .NET tool you can call from the shell/command line.
#tool dotnet:?package=fantomas&version=8.0.0-alpha-014&prerelease
                    
nuke :add-package fantomas --version 8.0.0-alpha-014
                    

Fantomas

Fantomas logo

GitHub Workflow Status (event) Discord Nuget (with prereleases)

An opinionated F# source code formatter.

dotnet tool install fantomas

Documentation is available at https://fsprojects.github.io/fantomas/docs/index.html

Contributing Guidelines

See the Contribution Guidelines and our contributors documentation

Product Compatible and additional computed target framework versions.
.NET net10.0 is compatible.  net10.0-android was computed.  net10.0-browser was computed.  net10.0-ios was computed.  net10.0-maccatalyst was computed.  net10.0-macos was computed.  net10.0-tvos was computed.  net10.0-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
8.0.0-alpha-018 0 8/26/2026
8.0.0-alpha-017 43 8/25/2026
8.0.0-alpha-016 251 8/25/2026
8.0.0-alpha-015 210 8/24/2026
8.0.0-alpha-014 107 8/20/2026
8.0.0-alpha-013 101 8/19/2026
8.0.0-alpha-012 6,764 4/16/2026
8.0.0-alpha-011 172 4/15/2026
8.0.0-alpha-010 168 4/15/2026
8.0.0-alpha-009 334 4/3/2026
8.0.0-alpha-008 177 3/25/2026
8.0.0-alpha-007 185 3/10/2026
8.0.0-alpha-006 150 3/9/2026
8.0.0-alpha-005 137 3/9/2026
8.0.0-alpha-004 131 3/7/2026
8.0.0-alpha-003 148 3/3/2026
8.0.0-alpha-002 389 12/15/2025
8.0.0-alpha-001 188 12/12/2025
7.0.6 2,749 8/19/2026
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### Changed

- Bump `StreamJsonRpc` to `2.25.29`. This clears the NuGet vulnerability warnings coming from the transitive `MessagePack` and `Nerdbank.MessagePack` dependencies. [#3393](https://github.com/fsprojects/fantomas/pull/3393)
- Breaking: `Expr.Chain` is redesigned around a head, a list of `ChainSegment` and a `ChainTerminal`. `Expr.DotLambda`, `Expr.DotIndexedGet`, `Expr.AppLongIdentAndSingleParenArg` and `Expr.NestedIndexWithoutDot` are removed, and a dotted long identifier now yields `Expr.Chain` instead of `Expr.OptVar` in expression position. See the [upgrade guide](https://fsprojects.github.io/fantomas/docs/end-users/UpgradeGuide.html) for how to migrate. [#3385](https://github.com/fsprojects/fantomas/pull/3385)
- Chains are laid out by a documented set of rules, written up in full under [Chains](https://fsprojects.github.io/fantomas/docs/contributors/Chains.html). They are a proposal for the F# style guide and may still change. A chain that fits on one line is left alone. When one has to break, only a call claims a line of its own and plain property access rides along in front of it, where a comment between the steps previously put every step on its own line. A long run of property access now wraps into balanced lines instead of overflowing the margin. [#3385](https://github.com/fsprojects/fantomas/pull/3385)
- With `fsharp_multi_line_lambda_closing_newline = false` (the default), a match lambda argument keeps `function` beside the `(` when the call is reached through a dot, matching what a call without a receiver already did. [#3385](https://github.com/fsprojects/fantomas/pull/3385)
- With `fsharp_multi_line_lambda_closing_newline = true`, a lambda argument whose opening line does not fit moves onto its own line instead of hanging its parameters under the opening parenthesis. This applies to calls with and without a receiver. [#3385](https://github.com/fsprojects/fantomas/pull/3385)
- Added `InvariantViolationException`, raised when Fantomas reaches a state its own model says is impossible. It derives from `FormatException`, carries the source range of the construct involved, and points at the issue tracker. [#3385](https://github.com/fsprojects/fantomas/pull/3385)

### Fixed

- CLI refuses to format files containing IWSAM types (warning 3535 fails output validation). [#3396](https://github.com/fsprojects/fantomas/issues/3396)
- A space was added before the parenthesis of a call inside a `_.` shorthand lambda when `fsharp_space_before_uppercase_invocation` was enabled, producing code that does not compile. [#3364](https://github.com/fsprojects/fantomas/issues/3364)