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https://issues.apache.org/jira/browse/ARROW-14999?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17581439#comment-17581439
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Dewey Dunnington commented on ARROW-14999:
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We do use metadata (extension type + metadata), although the definition of the
extension types is newer than the memory layout, which was the document that
proposed the list-child-name-conveying-information strategy. In practice the
prototype I wrote mostly ignores the list child names, with the exception being
the name of a point array which conveys its dimension (e.g., xy, xyz, xym, or
xyzm). Conveying the dimension of the point array using the name was done in
part to avoid a parser (to parse extension type metadata since it has to be
valid utf8) when writing C kernels (since 'name' at the C data array level is
just a null-terminated string). At the time we designed this there was no
indication that the roundtripping of the child name would be an issue; however,
we could certainly work around it.
> [C++] List types with different field names are not equal
> ---------------------------------------------------------
>
> Key: ARROW-14999
> URL: https://issues.apache.org/jira/browse/ARROW-14999
> Project: Apache Arrow
> Issue Type: Improvement
> Components: C++
> Affects Versions: 6.0.0
> Reporter: Will Jones
> Assignee: Will Jones
> Priority: Major
> Labels: pull-request-available
> Fix For: 10.0.0
>
> Time Spent: 10m
> Remaining Estimate: 0h
>
> When comparing map types, the names of the fields are ignored. This was
> introduced in ARROW-7173.
> However for list types, they are not ignored. For example,
> {code:python}
> In [6]: l1 = pa.list_(pa.field("val", pa.int64()))
> In [7]: l2 = pa.list_(pa.int64())
> In [8]: l1
> Out[8]: ListType(list<val: int64>)
> In [9]: l2
> Out[9]: ListType(list<item: int64>)
> In [10]: l1 == l2
> Out[10]: False
> {code}
> Should we make list type comparison ignore field names too?
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