100. Restriction on executory limitations.
Where a person is entitled under a will to -
(a) land for an estate in fee simple or for any lesser estate or interest not being an estate tail, or
(b) any interest in other property,
with an executory limitation over in default or failure of any of his issue, whether within a specified period of time or not, that executory limitation shall be or become void and incapable of taking effect, if and as soon as there is living any issue of the class in default or failure of which the limitation over was to take effect.