class Prime::PseudoPrimeGenerator

An abstract class for enumerating pseudo-prime numbers.

Concrete subclasses should override succ, next, rewind.

Public Class Methods

new(ubound = nil) click to toggle source

# File lib/prime.rb, line 237
def initialize(ubound = nil)
  @ubound = ubound
end

Public Instance Methods

each() { |prime| ... } click to toggle source

Iterates the given block for each prime number.

# File lib/prime.rb, line 269
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

next() click to toggle source

alias of succ.

# File lib/prime.rb, line 257
def next
  raise NotImplementedError, "need to define `next'"
end

rewind() click to toggle source

Rewinds the internal position for enumeration.

See Enumerator#rewind.

# File lib/prime.rb, line 264
def rewind
  raise NotImplementedError, "need to define `rewind'"
end

size() click to toggle source

# File lib/prime.rb, line 304
def size
  Float::INFINITY
end

succ() click to toggle source

returns the next pseudo-prime number, and move the internal position forward.

PseudoPrimeGenerator#succ raises NotImplementedError.

# File lib/prime.rb, line 252
def succ
  raise NotImplementedError, "need to define `succ'"
end

upper_bound() click to toggle source

# File lib/prime.rb, line 244
def upper_bound
  @ubound
end

upper_bound=(ubound) click to toggle source

# File lib/prime.rb, line 241
def upper_bound=(ubound)
  @ubound = ubound
end

with_index(offset = 0) { |prime, offset| ... } click to toggle source

see Enumerator#with_index.

# File lib/prime.rb, line 286
def with_index(offset = 0, &block)
  return enum_for(:with_index, offset) { Float::INFINITY } unless block
  return each_with_index(&block) if offset == 0

  each do |prime|
    yield prime, offset
    offset += 1
  end
end

with_object(obj) { |prime, obj| ... } click to toggle source

see Enumerator#with_object.

# File lib/prime.rb, line 297
def with_object(obj)
  return enum_for(:with_object, obj) { Float::INFINITY } unless block_given?
  each do |prime|
    yield prime, obj
  end
end