src/query.js
function binaryOperator(queryObject, actualField, key) {
    return actualField + OPS[key] + stringify(queryObject, actualField);
}
function binaryOperator(queryObject, actualField, key) {
    return actualField + OPS[key] + stringify(queryObject, actualField);
}
function binaryOperator ( queryObject , actualField , key ) { return actualField + OPS [ key ] + stringify ( queryObject , actualField ) ; }
Converts binary operator queries into string by applying operator and
recursively invokes parsing process for rvalue.

@param {object} queryObject Which contains the operator.
@param {string} actualField Current field of the object which the filter is operating on.
@param {string} key The current operation key.
@returns {string}
Converts binary operator queries into string by applying operator and recursively invokes parsing process for rvalue .