alamb opened a new issue, #8152: URL: https://github.com/apache/arrow-rs/issues/8152
**Is your feature request related to a problem or challenge? Please describe what you are trying to do.** - part of https://github.com/apache/arrow-rs/issues/6736 - As part of implementing shredded variants in `variant_get` https://github.com/apache/arrow-rs/issues/8083 there are cases where the code needs to assemble a Variant whose metadata is already known and can not be changed For example, when "shredding" a variant object, a new variant object is made with fields that are successfully shredded totally removed. The output variant object has the same metadata as the input variant (and can't change) but needs to have different actual fields. The existing `VariantBuilder` / `MetadataBuilder` allows new fields to be added (and thus change the Metadata), so it is not directly applicable **Describe the solution you'd like** A way to build variants with a pre-existing, read only, metadata. If a field is added to the the in progress object that is not present in the original metadata, then an error / panic should be raised. **Describe alternatives you've considered** @scovich has one proposal here (basically make MetadataBuilder a trait): - https://github.com/apache/arrow-rs/pull/7915 **Additional context** <!-- Add any other context or screenshots about the feature request here. --> -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: github-unsubscr...@arrow.apache.org.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
