Using map for non array objects

functionalExample.js

/*
This is a refactor from my previous job that I really like.  Before the refactor, I had declared at least 3 
different variables that were only necessary within the immediate function scope.  Then I tried nesting functions
passing arguments with arguments into arguments etc...

Using .map for objects other than arrays proves to be very useful here.  I no longer have to declare unneeded variables,
yet I still maintain readibility through a functional approach.  All that was needed was to wrap the object in brackets,
and then select the first index in that array at the end.

I have found this approach to be consistently useful.
*/

const queryStringWithoutPageParams = (router, resource, params) =>
  [(params || queryParams(router, resource)).query]
    .map(paramsWithPage => fromJS(paramsWithPage).set('page', {}).toJS())
    .map(paramsWithoutPage => queryStringBuilder(paramsWithoutPage))
    .map(queryStringWithoutPageParams => queryStringWithoutPageParams.slice(1))[0];