I Guess halving is going to be around 2019. And this will be priced in 2018 not 2019.
People will start to go long on bitcoin before halving day and on halving day too many investors will be in huge profit.
The next halving is scheduled to take place by 2020. Already 2020 has been expected to be something a great year in the cryptocurrency network. Along with this expectation the halving will provide with a large benefits as growth is promised to take place by those days. Hope to see the price to be above $30000 to the minimum by that time.