The span bound is an internal construction invariant: it asserts (debug builds) when the spans exceed the child length; the public validators (validateListChunk) throw DataFrameException for malformed chunks.
ListBuilder.finish
Seals the parent chunk over the given child.
Parameters
element | the element type (the child's dtype must match) |
child | the sealed child chunk holding every list's elements in append order |
Returns
the finished LIST chunk; the builder is spent.