[ARROW-10397] [C++] Outdated and confusing comment on dictionary indices

• Type: Bug
• Status: Resolved
• Priority: Trivial
• Resolution: Fixed
• Fix Version/s: 3.0.0
• Component/s: C++
• Labels: pull-request-available
• External issue URL: https://github.com/apache/arrow/issues/26380
• Assignee: Carol Nichols
• Reporter: Carol Nichols
• Created: 26/Oct/20 20:59
• Updated: 11/Jan/23 08:13
• Resolved: 28/Oct/20 02:57

Description

While working on the Rust implementation, I got confused by this comment that said dictionary index types could be assumed to be signed integers. The Rust code allowed for unsigned integers, so I thought the Rust code had a bug. However, I read the C++ code more carefully, and unsigned integers are allowed as dictionary index types-- this was changed in this commit but the comment wasn't updated.

I have a pull request fixing the comment, just want to save someone a few minutes of confusion

Issue Links

• links to: GitHub Pull Request #8535