Cross join nested data

[eddycharly]

What is the simplest way to transform data:

{
 "states": [
   {"name": "WA", "cities": ["Seattle", "Bellevue", "Olympia"]},
   {"name": "CA", "cities": ["Los Angeles", "San Francisco"]},
   {"name": "NY", "cities": ["New York City", "Albany"]}
 ]
}

Into:

[
  { "name": "WA", "city": "Seattle" },
  { "name": "WA", "city": "Bellevue" },
  { "name": "WA", "city": "Olympia" },
  { "name": "CA", "city": "Los Angeles" },
  { "name": "CA", "city": "San Francisco" },
  { "name": "NY", "city": "New York City" },
  { "name": "NY", "city": "Albany" }
]

That is, iterating over states and cities and producing one object per state and city combination ?

cc @springcomp 🙏

[springcomp]

@eddycharly

map(&let $n=name, $cs=cities in map(&{name: $n, city:@}, $cs), @.states)[]

[eddycharly]

Thanks @springcomp !

I was hoping there was a solution without using let, do you think it is possible ?

[springcomp]

Unfortunately, I do not think that is possible.