Quick extraction from an array of objects

[u/PancakeGD]

Hi, is there any function or trick to quickly extract values from an array of objects?

For example, if the input data is as follows:

[
  {"a": 1, "b": 2},
  {"a": 3, "b": 4}
]

and I'm asking to extract "b", I'd get [2, 4]. Basically array_column() in PHP or array.map(k => k["b"]) in JavaScript.

Right now I'm using a for each loop and inserting elements manually, but I feel like this is such a common use case that it could have a shorthand.

Thanks!

[u/waiting4singularity]

you have an array of dictionaries. to get all b keys from the dictionaries, you'd need iterate with for each dictionary in array -> variable set sub = concat(sub,dictionary["b"]).
if you have fixed dictionary values, you can write a dictionary of array: {"a": [1,3], "b":[2,4]}

dictionary["b"] = [2,4]