src/js/pagination/paging-collection.js
function(fieldName) {
                return _.has(this.filterableFields, fieldName) && !_.isNull(this.filterableFields[fieldName].value);
            }
function(fieldName) {
                return _.has(this.filterableFields, fieldName) && !_.isNull(this.filterableFields[fieldName].value);
            }
function ( fieldName ) { return _ . has ( this . filterableFields , fieldName ) && ! _ . isNull ( this . filterableFields [ fieldName ] . value ) ; }
Returns whether this collection has set a filterable field.

@param fieldName {string} querystring parameter name for the
filterable field
@return {boolean} Returns true if this collection has set the specified field.
Returns whether this collection has set a filterable field .