class Prime::PseudoPrimeGenerator
An abstract class for enumerating pseudo-prime numbers.
Concrete subclasses should override succ, next, rewind.
Public Class Methods
# File lib/prime.rb, line 233 def initialize(ubound = nil) @ubound = ubound end
Public Instance Methods
# File lib/prime.rb, line 265 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
Iterates the given block for each prime number.
# File lib/prime.rb, line 253 def next raise NotImplementedError, "need to define `next'" end
alias of succ
.
# File lib/prime.rb, line 260 def rewind raise NotImplementedError, "need to define `rewind'" end
Rewinds the internal position for enumeration.
See Enumerator
#rewind.
# File lib/prime.rb, line 300 def size Float::INFINITY end
# File lib/prime.rb, line 248 def succ raise NotImplementedError, "need to define `succ'" end
returns the next pseudo-prime number, and move the internal position forward.
PseudoPrimeGenerator
#succ raises NotImplementedError
.
# File lib/prime.rb, line 240 def upper_bound @ubound end
# File lib/prime.rb, line 237 def upper_bound=(ubound) @ubound = ubound end
# File lib/prime.rb, line 282 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
see Enumerator
#with_index.
# File lib/prime.rb, line 293 def with_object(obj) return enum_for(:with_object, obj) { Float::INFINITY } unless block_given? each do |prime| yield prime, obj end end
see Enumerator
#with_object.
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