Hi,
The Companies Act 2013, does not recognise share warrants explicitly though the RBI permits them to be issued to foreign investors, subject to certain conditions (You can look up the latest RBI notification on this). It is common practise for private companies to issue warrants to their foreign investors, especially for start ups.
Further, the recent June 29, 2016 notification from MCA has referred to a convertible note convertible into equity shares or repayable within a period not exceeding
five years from the date of issue) in a single tranche, from a person. (You can look up this notification for further details).
Regards
Supriya