Object
An abstract class for enumerating pseudo-prime numbers.
Concrete subclasses should override succ, next, rewind.
Iterates the given block for each prime number.
# File prime.rb, line 266
def each
return self.dup unless block_given?
if @ubound
last_value = nil
loop do
prime = succ
break last_value if prime > @ubound
last_value = yield prime
end
else
loop do
yield succ
end
end
end
alias of succ.
# File prime.rb, line 254
def next
raise NotImplementedError, "need to define `next'"
end
Rewinds the internal position for enumeration.
See Enumerator#rewind.
# File prime.rb, line 261
def rewind
raise NotImplementedError, "need to define `rewind'"
end
returns the next pseudo-prime number, and move the internal position forward.
PseudoPrimeGenerator#succ raises NotImplementedError.
# File prime.rb, line 249
def succ
raise NotImplementedError, "need to define `succ'"
end
# File prime.rb, line 238
def upper_bound=(ubound)
@ubound = ubound
end
see Enumerator#with_index.
# File prime.rb, line 283
def with_index(offset = 0)
return enum_for(:with_index, offset) { Float::INFINITY } unless block_given?
return each_with_index(&proc) if offset == 0
each do |prime|
yield prime, offset
offset += 1
end
end