Expression language: lookup equivalent for json arrays

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1

I have a tag, say tableTag, which is of type Document: it's an array of json objects, all objects with the same structure. I'd like to define some more tags which are expression tags and get their value from tableTag looking up a value in a key of the tableTag objects That looks like looking up a value in a dataset, but whereas the expression language has a lookup function for datasets, I cannot seem to find an equivalent function for json arrays. I developed a python script function of my own, called jsLookup and it works. But if I want to use it in an expression tag, my project must be the Gateway Scripting Project and that's not possible.

Any suggestion, except going back to datasets?

Thanks, regards

2

There's no lookup equivalent, but I think an expression like {document}[indexOf({lookup})] might work? Subscripts and the indexOf function should both work on arrays and documents.

3

Sounds like a job for a utility module....

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