dotnet / dotnet/dotnet-api-docs

Collections like Lists are cannot be used with HashCode.Combine(collection);

Open
#10,908 3 comments 0 reactions 0 assignees View on GitHub
area-System.Runtime untriaged
Dominant language
C#
Stars
949
Forks
1.7k
Avg merge
3d 27m
Merged PRs (30d)
49

Description

### Type of issue

Missing information

### Description

I spent a good deal of time trying to understand why my Distinct operations were not working for a newly created Type.
It turns out that the **HashCode.Combine(collection);** does not work, it works fine when the instances passed in are not collections, but the documentation doesn't say that clearly.
In my opinion there should be a type check in the method itself as this makes the code very dangerous as only at runtime the issue can be discovered.
I found it just because I was testing most of the equality features around my new type.

I'd be happy to know if I am missing something

### Page URL

https://learn.microsoft.com/en-us/dotnet/api/system.hashcode.combine?view=net-8.0#system-hashcode-combine-1(-0)

### Content source URL

https://github.com/dotnet/dotnet-api-docs/blob/main/xml/System/HashCode.xml

### Document Version Independent Id

4b23ab47-87c7-32b1-a0ca-9c13d5ec93e5

### Article author

@dotnet-bot

Contributor guide

Open the contributing guide

Assessment

This issue has not been assessed yet.

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.