On 17 June 2018 at 02:47, Sven Van Caekenberghe <sven@stfx.eu> wrote:

Hmm, Ben,

Did you see NeoJSONCustomMapping's mapping method category ?��

There you can already find #listOfElementSchema:�� #listOfType:��

#listOfType:andElementSchema: as well as #mapWithValueSchema:

Yes. Indeed thats where I copied my selector naming from, although I switched "with" for ''and"��

NeoJSONPropertyMapping >> listOfType:withElementSchema: ��

However NeoJSONCustomMappings seems only accessible through "reader for: ... customDo: "
while instance variable interaction seems only possible using "reader for: ... do:"��

So it seems NeoJSONCustomMapping��lacks #mapAccessor* methods

while NeoJSONObjectMapping lacks #listOfType:* methods

and "never the twain shall meet".

I didn't look closely at #mapWithValueSchema:

but its covering tests seem to operate on Dictionaries rather than Arrays.

��

I am guessing they do what you want, no ? Or am I missing something as well ?

Yes, but how to mix those list* methods��with poking the result into an instance variable

to be able to��"assign a list of elements to an instance variable" as a one liner?

I'd be glad to be shown another way to do this for the given data.

I see a few #testLists examples, but none that assign the result to an instance variable.

NeoJSONExamplesTests has some "lists of objects" tests, but no "objects with lists"

A useful example would be #testPolygonPoints...��

NeoJSONExamplesTests >> testPolygonPoints

| polygon polygonJson result |

polygon := Polygon new vertices: { 1@2. 3@4. 5@6 }.

polygonJson :=��

'{ "vertices": [�� "I'm not clear on how to do the writer side of things"

{

"x" : 1,

"y" : 2

{

"x" : 3,

"y" : 4

{

"x" : 5,

"y" : 6

}]

}'.

result := (NeoJSONReader on: polygonJson readStream)

mapInstVarsFor: Point;

for: Polygon do: [ :mapping |��

(mapping mapInstVar: #vertices) listOfType: Array withElementSchema: Point];

nextAs: Polygon.

self assert: result equals: polygon

Some equality support is��needed for��Polygon (PathShape)
(my best guess, discussion of this might be worth a separate thread)

PathShape >> = aPathShape

|otherVertices equal|

otherVertices := aPathShape vertices.

(self species = aPathShape species) & (vertices size = otherVertices size)��

ifFalse: [ ^false ].

1 to: vertices size do: [ :i |��

(vertices at: i) = (otherVertices at: i) ifFalse: [^false] ].

^true

PathShape >> hash

|hash|

hash := 0.

1 to: vertices size do: [ :i | hash bitXor: (vertices at: i) ].

^hash��

cheers -ben

��

Sven

> On 16 Jun 2018, at 20:27, Ben Coman <btc@openinworld.com> wrote:
>
> hi Sven,
>
> With NeoJSON I have found several times in handling lists that
> I need to indirect through�� #for:customDo:�� like this......
>
>�� reader
>�� for: ExercismProblems
>�� do: [ :mapping |
>�� self halt.
>�� (mapper mapInstVar: #problems) valueSchema: #ArrayOfProblems ].
>�� reader
>�� for: #ArrayOfProblems
>�� customDo: [�� :mapping |
>�� mapper listOfElementSchema: ExercismProblem ].
>
>
> when I'd really like to be simpler and more concise like this...
>
>�� reader
>�� for: ExercismProblems
>�� do: [ :mapping |
>�� (mapping mapInstVar: #problems) listOfType: Array withElementSchema: ExercismProblem ].
>
> so I'm seeking your feedback on the following hack which facilitates that.
> (and if I missed something that already makes it simpler)
>

cheers -ben