Pick keys of result similarly to $..book[0][category,author]

[fgodino]

First of all, awesome library this has helped us so much.

I would like to suggest a new feature to return a filtered result selecting the keys. Right now, if we use $..book[0][category,author] it returns a list of results with the values of the object keys in the result. Taking the example $..book[0][category,author], it returns

[ 'reference',
  'Nigel Rees',
  'fiction',
  'Evelyn Waugh',
  'fiction',
  'Herman Melville',
  'fiction',
  'J. R. R. Tolkien' ]

It would be great if we could add a feature to show the actual filtered object bases on these keys. Something like:

[ { category: 'reference', author: 'Nigel Rees' },
  { category: 'fiction', author: 'Evelyn Waugh' },
  { category: 'fiction', author: 'Herman Melville' },
  { category: 'fiction', author: 'J. R. R. Tolkien' } ]

For syntax, it could be like this: $..book[0]{category,author} or this: $..book[0]{category: expr,author:expr}

Let me know what you think.

Thank you!

[brettz9]

While there have been some minor improvements, I haven't had time to develop this library.

I don't know how well it performs, but you might take a look at http://docs.jsonata.org , specifically http://docs.jsonata.org/predicate . By a quick look of things, this looks like a nice, full featured alternative.