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instance method
Set#proper_subset?
(self) -> bool
proper_subset?(other_set) → true or false
set.c
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static VALUE
set_i_proper_subset(VALUE set, VALUE other)
{
check_set(other);
if (RSET_SIZE(set) >= RSET_SIZE(other)) return Qfalse;
return set_le(set, other);
}
Returns whether self is a proper subset of the given other_set:
Example
set = Set[*'b'..'e'] set.proper_subset?(set) # => false set.proper_subset?(Set[*'a'..'f']) # => true
Related: Methods for Querying.