wjones127 commented on a change in pull request #166:
URL: https://github.com/apache/arrow-cookbook/pull/166#discussion_r831242717
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File path: cpp/source/basic.rst
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@@ -48,3 +48,58 @@ boilerplate for you. It will run the contained expression
and check the resulti
.. recipe:: ../code/basic_arrow.cc ReturnNotOk
:caption: Using ARROW_RETURN_NOT_OK to check the status
:dedent: 2
+
+
+Using the Visitor Pattern
+=========================
+
+Arrow classes DataType, Scalar, and Array have specialized subclasses for
+each Arrow type. In order to specialize logic for each subclass, you the
visitor
+pattern. Arrow provides the macros:
+
+ * `arrow::VisitTypeInline`
+ * `arrow::VisitScalarInline`
+ * `arrow::VisitArrayInline`
+
+To implement a TypeVisitor we have to implement a Visit method for every
possible
+DataType we wish to handle. Fortunately, we can often use templates and type
+traits to make this less verbose.
+
+Generate Random Data for Given Schema
+-------------------------------------
+
+To generate random data for a given schema, a type visitor is helpful.
+
+
+.. literalinclude:: ../code/basic_arrow.cc
+ :language: cpp
+ :linenos:
+ :start-at: class RandomBatchGenerator
+ :end-at: }; // RandomBatchGenerator
+ :caption: Using visitor pattern to generate random record batches
+
+
+.. recipe:: ../code/basic_arrow.cc GenerateRandomData
+ :dedent: 2
+
+
+Convert Arbitrary Scalars to Variants
+-------------------------------------
+
+.. TODO: Implement converter from rows to values
Review comment:
I'll delete this. I was initially thinking of doing three examples, but
I think the two I've done seem fine.
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