GH-50294: [C++][R] Missing typename in ulp_distance.cc breaks clang-15 builds

[thisisnic]

Rationale for this change

Broken nightlies due to older clang version on CRAN

What changes are included in this PR?

Add typename explicitly

Are these changes tested?

Will run CI

Are there any user-facing changes?

No

• GitHub Issue: [C++][R] Missing typename in ulp_distance.cc breaks clang-15 builds #50294

[github-actions]

⚠️ GitHub issue #50294 has been automatically assigned in GitHub to PR creator.

[github-actions]

⚠️ GitHub issue #50294 has no components, please add labels for components.

[thisisnic]

@github-actions crossbow submit test-r-linux-as-cran

[Copilot]

Pull request overview

This PR fixes a C++ template-dependent type issue that breaks older clang builds, and also expands Arrow R/Python support for view-based string/binary types to improve round-tripping and dictionary handling.

Changes:

• Fix clang-15 build failure by adding missing typename to a dependent type in ulp_distance.cc.
• Add R type bindings + conversion support for string_view / binary_view, including dictionary round-trips.
• Update Python dictionary conversion for string-view-like values and add/extend tests/docs/exports for the new R types.

Reviewed changes

Copilot reviewed 1 out of 1 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
r/tests/testthat/test-Table.R	Adds Table-level round-trip tests for string_view and binary_view (incl. dictionary).
r/tests/testthat/test-data-type.R	Adds datatype behavior tests for string_view and binary_view; includes code roundtrip coverage.
r/tests/testthat/test-Array.R	Adds Array round-trip tests for string_view and binary_view (incl. long values).
r/src/r_to_arrow.cpp	Extends R→Arrow conversion to handle StringView and BinaryView-like builders safely.
r/src/datatype.cpp	Adds R6 class mapping + exported initializers for utf8_view / binary_view.
r/src/arrowExports.cpp	Registers new exported C++ entry points for the added R datatypes.
r/src/array_to_vector.cpp	Extends Arrow→R conversion to support STRING_VIEW and BINARY_VIEW arrays and dictionary level coercion.
r/R/type.R	Adds utf8_view() / string_view() and binary_view() to the R API + canonical type string mapping.
r/R/arrowExports.R	Adds R .Call() wrappers for the new datatype initializers.
r/NAMESPACE	Exports utf8_view, string_view, and binary_view.
r/man/data-type.Rd	Documents the new datatype helpers.
python/pyarrow/src/arrow/python/python_to_arrow.cc	Adjusts dictionary conversion to append via std::string_view for string-view-like values.
cpp/src/arrow/util/ulp_distance.cc	Adds missing typename for clang compatibility.
cpp/src/arrow/util/converter.h	Enables dictionary conversion support for StringViewType / BinaryViewType.

[github-actions]

Revision: 98da882

Submitted crossbow builds: ursacomputing/crossbow @ actions-505abd297a

Task	Status
test-r-linux-as-cran

[Copilot]

Pull request overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated no new comments.

[pitrou]

I see you marked it as draft, but LGTM anyway :)

[thisisnic]

Ah sorry, I marked it as draft as I'd made a mistake and the issue is our CI is out date so the fix might not be needed to the code but to the CI instead. But I guess the fix isn't wrong, just now unnecessary? Looks like it's good practice so I'll just open a new issue for the CI update and merge this.

[thisisnic]

CI failure unrelated so I'll merge

[conbench-apache-arrow]

After merging your PR, Conbench analyzed the 4 benchmarking runs that have been run so far on merge-commit 681ef42.

There were no benchmark performance regressions. 🎉

The full Conbench report has more details.