Class: Transformer::Lazy

Inherits:

Object

• Object
• Transformer::Lazy

Defined in:

lib/coroutines/base.rb

Defined Under Namespace

Classes: Yielder

Instance Method Summary

• #count ⇒ Object
• #drop(n) ⇒ Object
• #drop_while(&block) ⇒ Object
• #each(&block) ⇒ Object
• #filter_map(&block) ⇒ Object
• #flat_map(&block) ⇒ Object (also: #collect_concat)
• #initialize(trans) ⇒ Lazy constructor

  A new instance of Lazy.

• #lazy ⇒ Object
• #map(&block) ⇒ Object (also: #collect)
• #out_connect(other) ⇒ Object
• #reduce(*args) ⇒ Object (also: #inject)
• #reject(&block) ⇒ Object
• #select(&block) ⇒ Object
• #sort ⇒ Object
• #sort_by(&block) ⇒ Object
• #take(n) ⇒ Object
• #take_while(&block) ⇒ Object
• #to_a ⇒ Object
• #to_h ⇒ Object

Constructor Details

#initialize(trans) ⇒ Lazy

Returns a new instance of Lazy.

# File 'lib/coroutines/base.rb', line 247

def initialize(trans)
	@trans = trans.instance_variable_get :@self
end

Instance Method Details

#count ⇒ Object

# File 'lib/coroutines/base.rb', line 271

def count
	Consumer.new do |y|
		yy = Yielder.new y
		n = 0
		yy.define_yield do |*values|
			n += 1
			yy
		end
		@trans.call yy
		n
	end
end

#drop(n) ⇒ Object

# File 'lib/coroutines/base.rb', line 284

def drop(n)
	Transformer.new do |y|
		yy = Yielder.new y
		to_drop = n
		yy.define_yield do |*values|
			if to_drop > 0
				to_drop -= 1
			else
				y.yield(*values)
			end
			yy
		end
		@trans.call yy
	end
end

#drop_while(&block) ⇒ Object

# File 'lib/coroutines/base.rb', line 300

def drop_while(&block)
	Transformer.new do |y|
		yy = Yielder.new y
		dropping = true
		yy.define_yield do |*values|
			if dropping
				if not block.call(*values)
					dropping = false
					y.yield(*values)
				end
			else
				y.yield(*values)
			end
			yy
		end
		@trans.call yy
	end
end

#each(&block) ⇒ Object

# File 'lib/coroutines/base.rb', line 319

def each(&block)
	Consumer.new do |y|
		yy = Yielder.new y
		yy.define_yield do |*values|
			block.call(*values)
			yy
		end
		@trans.call yy
	end
end

#filter_map(&block) ⇒ Object

# File 'lib/coroutines/base.rb', line 330

def filter_map(&block)
	Transformer.new do |y|
		yy = Yielder.new y
		yy.define_yield do |*values|
			x = block.call(*values)
			y.yield(x) unless x.nil?
			yy
		end
		@trans.call yy
	end
end

#flat_map(&block) ⇒ Object Also known as: collect_concat

# File 'lib/coroutines/base.rb', line 342

def flat_map(&block)
	Transformer.new do |y|
		yy = Yielder.new y
		yy.define_yield do |*values|
			x = block.call(*values)
			if x.respond_to? :to_ary
				x.to_ary.each{|xx| y.yield xx }
			else
				y.yield x
			end
			yy
		end
		@trans.call yy
	end
end

#lazy ⇒ Object

# File 'lib/coroutines/base.rb', line 251

def lazy
	self
end

#map(&block) ⇒ Object Also known as: collect

# File 'lib/coroutines/base.rb', line 359

def map(&block)
	Transformer.new do |y|
		yy = Yielder.new y
		yy.define_yield do |*values|
			y.yield(block.call(*values))
			yy
		end
		@trans.call yy
	end
end

#out_connect(other) ⇒ Object

# File 'lib/coroutines/base.rb', line 371

def out_connect(other)
	Transformer.new(&@trans).out_connect(other)
end

#reduce(*args) ⇒ Object Also known as: inject

Raises:

• (ArgumentError)

# File 'lib/coroutines/base.rb', line 375

def reduce(*args)
	if not block_given?
		if args.size == 1
			return reduce(&args[0].to_proc)
		elsif args.size == 2
			return reduce(args[0], &args[1].to_proc)
		else
			raise ArgumentError, "wrong number of arguments"
		end
	end
	raise ArgumentError, "wrong number of arguments" if args.size > 1
	block = proc

	memo = if args.empty? then nil else args[0] end
	Consumer.new do |y|
		yy = Yielder.new y
		yy.define_yield do |value|
			if memo.nil?
				memo = value
			else
				memo = block.call memo, value
			end
			yy
		end
		@trans.call yy
		memo
	end
end

#reject(&block) ⇒ Object

# File 'lib/coroutines/base.rb', line 405

def reject(&block)
	Transformer.new do |y|
		yy = Yielder.new y
		yy.define_yield do |*values|
			y.yield(*values) unless block.call(*values)
			yy
		end
		@trans.call yy
	end
end

#select(&block) ⇒ Object

# File 'lib/coroutines/base.rb', line 416

def select(&block)
	Transformer.new do |y|
		yy = Yielder.new y
		yy.define_yield do |*values|
			y.yield(*values) if block.call(*values)
			yy
		end
		@trans.call yy
	end
end

#sort ⇒ Object

# File 'lib/coroutines/base.rb', line 459

def sort
	Consumer.new do |y|
		yy = Yielder.new y
		result = []
		yy.define_yield do |value|
			result << value
			yy
		end
		@trans.call yy
		result.sort
	end
end

#sort_by(&block) ⇒ Object

# File 'lib/coroutines/base.rb', line 472

def sort_by(&block)
	Consumer.new do |y|
		yy = Yielder.new y
		result = []
		yy.define_yield do |value|
			result << value
			yy
		end
		@trans.call yy
		result.sort_by(&block)
	end
end

#take(n) ⇒ Object

# File 'lib/coroutines/base.rb', line 427

def take(n)
	Transformer.new do |y|
		yy = Yielder.new y
		to_take = n
		yy.define_yield do |*values|
			if to_take > 0
				y.yield(*values)
				to_take -= 1
			else
				raise StopIteration
			end
			yy
		end
		@trans.call yy
	end
end

#take_while(&block) ⇒ Object

# File 'lib/coroutines/base.rb', line 444

def take_while(&block)
	Transformer.new do |y|
		yy = Yielder.new y
		yy.define_yield do |*values|
			if block.call(*values)
				y.yield(*values)
			else
				raise StopIteration
			end
			yy
		end
		@trans.call yy
	end
end

#to_a ⇒ Object

# File 'lib/coroutines/base.rb', line 485

def to_a
	Consumer.new do |y|
		yy = Yielder.new y
		result = []
		yy.define_yield do |value|
			result << value
			yy
		end
		@trans.call yy
		result
	end
end

#to_h ⇒ Object

# File 'lib/coroutines/base.rb', line 498

def to_h
	Consumer.new do |y|
		yy = Yielder.new y
		result = {}
		yy.define_yield do |value|
			result[value[0]] = value[1]
			yy
		end
		@trans.call yy
		result
	end
end