Section Section 17
, sub-section (1), and clauses (a) and (b) of section 18, shall, if duly registe
section 17, sub-section (1), and clauses (a) and (b) of section 18, shall, if duly registered, take effect as regards the property comprised therein, against every unregistered document relating to the same property, and not being a decree O order, whether such unregistered document be of the same nature as the registered document O not: (2) Nothing in sub-section (/) applies to leases exempted under the proviso to sub-section (1) of