[#8A7A8237F82E01A1EEC9EAF31E15DF5CC07CCC61]
Insert elements
iterator insert( iterator before, param_view const& p);
This function inserts a param before the specified position.
All iterators that are equal to `before` or come after are invalidated.
Linear in `this->url().encoded_query().size()`.
Strong guarantee. Calls to allocate may throw.