jkosh44 commented on code in PR #14532:
URL: https://github.com/apache/datafusion/pull/14532#discussion_r1945901504
##########
datafusion/expr-common/src/signature.rs:
##########
@@ -227,25 +226,11 @@ impl Display for TypeSignatureClass {
#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Hash)]
pub enum ArrayFunctionSignature {
- /// Specialized Signature for ArrayAppend and similar functions
- /// The first argument should be List/LargeList/FixedSizedList, and the
second argument should be non-list or list.
- /// The second argument's list dimension should be one dimension less than
the first argument's list dimension.
- /// List dimension of the List/LargeList is equivalent to the number of
List.
- /// List dimension of the non-list is 0.
- ArrayAndElement,
- /// Specialized Signature for ArrayPrepend and similar functions
- /// The first argument should be non-list or list, and the second argument
should be List/LargeList.
- /// The first argument's list dimension should be one dimension less than
the second argument's list dimension.
- ElementAndArray,
- /// Specialized Signature for Array functions of the form (List/LargeList,
Index+)
- /// The first argument should be List/LargeList/FixedSizedList, and the
next n arguments should be Int64.
- ArrayAndIndexes(NonZeroUsize),
- /// Specialized Signature for Array functions of the form (List/LargeList,
Element, Optional Index)
- ArrayAndElementAndOptionalIndex,
- /// Specialized Signature for ArrayEmpty and similar functions
- /// The function takes a single argument that must be a
List/LargeList/FixedSizeList
- /// or something that can be coerced to one of those types.
- Array,
+ /// A function takes at least one List/LargeList/FixedSizeList argument.
+ Array {
+ /// A full list of the arguments accepted by this function.
+ arguments: Vec<ArrayFunctionArgument>,
+ },
Review Comment:
One drawback of this structure is that someone can technically create a
signature with no array, only for it to get rejected at runtime in
`get_valid_types()`. An alternative structure could be:
```Rust
/// A list of arguments that come before the array.
pre_array_aguments: Vec<ArrayFunctionArgument>,
/// A list of arguments that come after the array.
post_array_aguments: Vec<ArrayFunctionArgument>,
```
Then we would remove the `ArrayFunctionArgument::Array` variant. This would
have the draw back of only allowing a single array argument in the signature,
which might be fine.
--
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...@datafusion.apache.org
For queries about this service, please contact Infrastructure at:
us...@infra.apache.org
---------------------------------------------------------------------
To unsubscribe, e-mail: github-unsubscr...@datafusion.apache.org
For additional commands, e-mail: github-h...@datafusion.apache.org
