An abstract class for enumerating pseudo-prime numbers.
Concrete subclasses should override succ, next, rewind.
# File rake/lib/prime.rb, line 244 def initialize(ubound = nil) @ubound = ubound end
Iterates the given block for each prime numbers.
# File rake/lib/prime.rb, line 276 def each(&block) return self.dup unless block if @ubound last_value = nil loop do prime = succ break last_value if prime > @ubound last_value = block.call(prime) end else loop do block.call(succ) end end end
alias of succ
.
# File rake/lib/prime.rb, line 264 def next raise NotImplementedError, "need to define `next'" end
Rewinds the internal position for enumeration.
See Enumerator
#rewind.
# File rake/lib/prime.rb, line 271 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 rake/lib/prime.rb, line 259 def succ raise NotImplementedError, "need to define `succ'" end
# File rake/lib/prime.rb, line 251 def upper_bound @ubound end
# File rake/lib/prime.rb, line 248 def upper_bound=(ubound) @ubound = ubound end
see Enumerator
#with_object.
# File rake/lib/prime.rb, line 296 def with_object(obj) return enum_for(:with_object) unless block_given? each do |prime| yield prime, obj end end