Remove the map function on JsonNode

[cjdxhjj]

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Describe the bug

The new version has added a map function to JsonNode for transforming JsonNode. I frequently use Kotlin, and since JsonNode implements Iterable, I could conveniently use node.map { it.xx } for a JsonArray to process each JsonNode and obtain a List. However, the newly added map function has overridden the map operator from Iterable with the one defined on JsonNode itself. As a result, I have to use much more verbose syntax, such as:

private fun <T> JsonNode.mapArray(fn: (JsonNode) -> T): List<T> = IntRange(0, size() - 1).map { fn(get(it)) }

I then renamed it to mapArr to avoid conflicts. While the native map operator on JsonNode has some use cases, I believe it is far less functional and practical than the map operator from Iterable.

When I upgrade to the new version, I have to adjust my original code.

Version Information

3.1.0

Reproduction

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Expected behavior

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Additional context

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[cowtowncoder]

Due to addition in 3.1 this is part of public API and removal only allowed in a Major version (4.0).

Timelines being what they are, this could happen in 5+ years or so (from 2.0 to 3.0 took over 10 years).

I can leave this open but realistically speaking this is unlike to be ever done.

[cjdxhjj]

Should we add another operation for converting JsonArray? The map method on JsonNode feels really useless, like jo.map(x -> xxxx). It would be better to have something like jo.xxx instead. After all, the JsonNode type is already fixed.

[cjdxhjj]

@cowtowncoder Could you add a conversion operation suitable for JSON arrays, like mapIter, since "map" is already in use? It would be much better than having to write this

private fun <T> JsonNode.mapArray(fn: (JsonNode) -> T): List<T> = IntRange(0, size() - 1).map { fn(get(it)) } 

everywhere.

[cowtowncoder]

@cjdxhjj I'd need Java version of this. I assume this would be for transforming ArrayNode elements?

Also, should file a new issue; would be considered & discussed separately from topic of this issue.

[cjdxhjj]

Yes, it is a conversion operation acting on an ArrayNode, which transforms each item of the ArrayNode and finally returns a list.