Clone knex instance

Is it possible to clone a knex instance, in order to reuse code?. For example, supose we have:

var query = knex('some-table as t1')
  .select('something')
  .join('other-table as t2', 't1.id', '=', 't2.t1_id');

function where1() {
  //reuse previous joins in query, 
  //but with specific where
  var q = query.clone()
    .where('t1.a', '=', 1);
  q.exec(function(err, response) {
    //do something
  });
}

function where1() {
  //reuse previous joins in query, 
  //but with specific where and join
  var q = query.clone()
    .join('third-table as t3', 't2.id', '=', 't3.t2_id')
    .where('t3.b', '=', 1);
  q.exec(function(err, response) {
    //do something
  });
}

Thanks.

[rcrogers]

Knex is great, but mutability and a fluent/chainable API makes a dangerous and counter-intuitive combination. Registering interest in a immutableQueryBuilder: true option.

[lorefnon]

@elhigu Do you think there is value in the following approach:

1. Knex QueryBuilder supports an intermediate JSON/serializable representation (along with fromJSON and toJSON functions) and internals (Query compiler etc.) depend on this JSON.

2. Two query builder implementations (mutable and immutable) can target the same representation internally with same (or almost same) APIs.

3. Over time the mutable one can be deprecated if there are no obvious performance concerns.

If this is something that can potentially be adopted, I can fiddle around this over the next couple weeks to gauge how much effort and testing will be required.