CollectionExpressionKiller 1.0.0

There is a newer version of this package available.
See the version list below for details.

dotnet add package CollectionExpressionKiller --version 1.0.0

NuGet\Install-Package CollectionExpressionKiller -Version 1.0.0

This command is intended to be used within the Package Manager Console in Visual Studio, as it uses the NuGet module's version of Install-Package.

<PackageReference Include="CollectionExpressionKiller" Version="1.0.0">
  <PrivateAssets>all</PrivateAssets>
  <IncludeAssets>runtime; build; native; contentfiles; analyzers</IncludeAssets>
</PackageReference>

For projects that support PackageReference, copy this XML node into the project file to reference the package.

<PackageVersion Include="CollectionExpressionKiller" Version="1.0.0" />
                    

                            Directory.Packages.props

<PackageReference Include="CollectionExpressionKiller">
  <PrivateAssets>all</PrivateAssets>
  <IncludeAssets>runtime; build; native; contentfiles; analyzers</IncludeAssets>
</PackageReference>
                    

                            Project file

For projects that support Central Package Management (CPM), copy this XML node into the solution Directory.Packages.props file to version the package.

paket add CollectionExpressionKiller --version 1.0.0

The NuGet Team does not provide support for this client. Please contact its maintainers for support.

#r "nuget: CollectionExpressionKiller, 1.0.0"

#r directive can be used in F# Interactive and Polyglot Notebooks. Copy this into the interactive tool or source code of the script to reference the package.

#:package CollectionExpressionKiller@1.0.0

#:package directive can be used in C# file-based apps starting in .NET 10 preview 4. Copy this into a .cs file before any lines of code to reference the package.

#addin nuget:?package=CollectionExpressionKiller&version=1.0.0
                    

                            Install as a Cake Addin

#tool nuget:?package=CollectionExpressionKiller&version=1.0.0
                    

                            Install as a Cake Tool

The NuGet Team does not provide support for this client. Please contact its maintainers for support.

Collection Expression Killer for C#

Ensures Explicit Coding Style for Code Review

</div>

Why?

Collection expression is useful for small scripts, demonstrations or other non-critical use cases but it is unclear what is actually created behind the scenes.

The source code should be explicitly expressing itself and eliminating "Something working" from the repository is important especially on code review on GitHub (no IDE assist).

Installation

dotnet add package CollectionExpressionKiller

`.editorconfig` Recommendation

Disable the suggestions relating to collection expressions.

dotnet_diagnostic.IDE0300.severity = silent   # Use collection expression for array
dotnet_diagnostic.IDE0301.severity = silent   # Use collection expression for empty
dotnet_diagnostic.IDE0305.severity = silent   # Use collection expression for fluent
dotnet_diagnostic.IDE0028.severity = silent   # Use collection initializers

Diagnostics

Ability to disallow all expressions or complicated only.

CEK001: Disallow all collection expressions.
CEK002: Disallow expressions with 4 or more elements. (e.g., [1, 2, ..other, 4])
CEK003: Disallow expressions whose string representation is longer than 12 characters.

How to Disable Analyzer

Disable for entire .cs file with #pragma:

#pragma warning disable CEK001
#pragma warning disable CEK002
#pragma warning disable CEK003

int[] values = [1, 2, 3, 4, ..otherCollection];

Disable for entire assembly:

using System.Diagnostics.CodeAnalysis;

[assembly: SuppressMessage(
    "Usage",
    "CEK001:Collection expressions are not allowed",
    Justification = "Approved for this assembly")]

[assembly: SuppressMessage(
    "Usage",
    "CEK002:Collection expressions must have fewer than 4 elements",
    Justification = "Approved for this assembly")]

[assembly: SuppressMessage(
    "Usage",
    "CEK003:Collection expression text length must be 12 or fewer characters",
    Justification = "Approved for this assembly")]

Disable for entire project with .editorconfig:

dotnet_diagnostic.CEK001.severity = none
dotnet_diagnostic.CEK002.severity = none
dotnet_diagnostic.CEK003.severity = none

There are no supported framework assets in this package.

Learn more about Target Frameworks and .NET Standard.

.NETStandard 2.0
- No dependencies.

NuGet packages

This package is not used by any NuGet packages.

GitHub repositories

This package is not used by any popular GitHub repositories.

Version	Downloads	Last Updated
1.3.0	81	2/26/2026
1.2.0	92	2/13/2026
1.1.0	86	2/12/2026
1.0.0	96	2/11/2026

https://github.com/sator-imaging/CollectionExpressionKiller