„README.md“ ändern

Argument for #reduce removed and everytime it will be an Array.

.gitignore

@@ -0,0 +1,2 @@
+functional.gemspec
+pkg

README.md

@@ -1,3 +1,8 @@
+Obsolete
+========
+
+Use `#lazy`.
+
 Install
 =======
 
@@ -8,8 +13,88 @@ Usage
 
 	require 'functional'
 	
-	obj = 0 .. 10**12
+	# To demonstrate Functional, we create a Class with a infinite loop:
-	Functional.new( obj).select {|i| i.even? }.collect {|i| i/3 }.select {|i| i.even? }.each &method( :puts)
+	class Sequence
+		include Enumerable
+		def initialize first = 0, step = 1
+			@i, @step = first, step
+		end
+		def each
+			# Our infinite loop:
+			loop do
+				yield @i
+				@i += @step
+			end
+		end
+	end
+	
+	Functional.new( Sequence.new).
+		select {|i| i.even? }.
+		collect {|i| i/3 }.
+		select {|i| i.even?}.
+		collect {|i| [[[[[[i.even?, i.odd?]]], i, [[[[[[i.class]]]]]]]]] }.
+		flatten. # It flattens everything! Not like: collect {|i| i.flatten }.
+		p
+	
+	# Without Functional... Bye bye.
+	Sequence.new.
+		select {|i| i.even? }.
+		collect {|i| i/3 }.
+		select {|i| i.even?}.
+		collect {|i| [[[[[[i.even?, i.odd?]]], i, [[[[[[i.class]]]]]]]]] }.
+		flatten. # It flattens everything! Not like: collect {|i| i.flatten }.
+		p
+
+It will never realize, that #p doesn't exists, because the first select runs endless.
+Functional#p prints everything to stdout.
+
+	(0..100000).to_fun.
+		collect {|i| i*3 }.
+		select {|i| i%5 == 2 }.
+		to_a
+
+Thanks to `Symbol#to_proc`:
+
+	Sequence.new.to_fun.
+		select( &:even?).
+		collect {|i| i/3 }.
+		select( &:even?).
+		collect {|i| [[[[[[i.even?, i.odd?]]], i, [[[[[[i.class]]]]]]]]] }.
+		flatten. # It flattens everything! Not like: collect {|i| i.flatten }.
+		p
+
+If you know methodphitamine,  combine it:
+
+	require 'methodphitamine'
+	
+	Sequence.new.to_fun.
+		select( &it.even?).
+		collect( &it/3).
+		select( &it.even?).
+		collect {|i| [[[[[[i.even?, i.odd?]]], i, [[[[[[i.class]]]]]]]]] }.
+		flatten.
+		p
+
+	(0..100000).to_fun.
+		collect( &it*3).
+		select( &it%5 == 2).
+		to_a
+
+Makros
+======
+
+	seq = Sequence.new.to_fun
+	seq = seq.select &it.even?  if must_be_even
+	seq = seq.
+		collect( &it/3).
+		select( &it.even?).
+		collect {|i| [[[[[[i.even?, i.odd?]]], i, [[[[[[i.class]]]]]]]]] }
+	seq = seq.flatten  if please_flatten
+	if print_it
+		seq.p
+	else
+		seq_to_a
+	end
 
 What's with _#map_?
 =================

VERSION

@@ -1 +1 @@
-0.0.1
+0.1.5

lib/functional.rb

@@ -1,46 +1,465 @@
-
+class ::Regexp
-class Functional
+	class NegRegexp
-	include Enumerable
+		def initialize r
-
+			@rx = r
-	def self.method_missing meth, *args, &exe
+		end
-		self.new.send meth, *args, &exe
+		def match l
+			! @rx.match( l)
+		end
+		def =~ l
+			! @rx =~ l
+		end
+		def -@
+			@rx
+		end
 	end
 
-	def push_method code, *args, &exe
+	def -@
-		name = "__meth_#{exe.object_id}"
+		NegRegexp.new self
-		define_singleton_method name, &exe
+	end
-		@stack.push [code % name]+args
+end
+
+class ::Object
+	def to_fun meth = nil
+		Functional.new self, meth
+	end
+end
+
+class Counter
+	include Enumerable
+	attr_reader :c
+
+	def initialize first = nil, step = nil
+		@c, @step = first || 0, step || 1
+	end
+
+	def next; @c += @step end
+	def to_i; c.to_i end 
+	def to_f; c.to_f end
+
+	def + i
+		@c += @step*i
+	end
+
+	def each &e
+		loop { e.call self; self.next }
+	end
+end
+
+class Functional
+	def self.__version__() '0.1.5' end
+	include Enumerable
+
+	class DEFAULT
+	end
+
+	class Base
+		attr_reader :exe
+		attr_accessor :next
+		attr_reader :caller
+
+		def initialize &e
+			@caller = Kernel.caller.first
+			@exe = e
+		end
+
+		def base_fun *a
+			@next.call *a
+		end
+		alias call base_fun
+
+		def end
+			@next.end
+		end
+
+		def clean
+			@next.clean
+		end
+
+		def to_proc
+			method( :call).to_proc
+		end
+	end
+
+	class Collect <Base
+		def collect_fun *a
+			@next.call *@exe.call( *a)
+		end
+		alias call collect_fun
+	end
+
+	class Tap <Base
+		def tap_fun *a
+			@exe.call *a
+			@next.call *a
+		end
+		alias call tap_fun
+	end
+
+	class Select <Base
+		def select_fun *a
+			@next.call *a  if @exe.call *a
+		end
+		alias call select_fun
+	end
+
+	class Filter <Base
+		def filter_fun *a
+			@next.call *a  unless @exe.call *a
+		end
+		alias call filter_fun
+	end
+
+	class Compact <Base
+		def compact_fun *a
+			@next.call *a  unless a.empty? || [nil] == a
+		end
+		alias call compact_fun
+	end
+
+	class BottomUp <Base
+		def initialize start, *a, &e
+			@next.call *a, &e
+			@buffer, @start = nil, start
+		end
+
+		def bottom_up_fun a
+			if @exe.call a
+				@next.call @buffer+a
+				@buffer = @start.dup
+			else
+				@buffer += a
+			end
+		end
+		alias call bottom_up_fun
+
+		def end
+			@next.call @buffer
+			@next.end
+		end
+	end
+
+	class TopDown <Base
+		def initialize start, *a, &e
+			@next.call *a, &e
+			@buffer, @start = nil, start
+		end
+
+		def top_down_fun a
+			if @exe.call a
+				@next.call @buffer
+				@buffer = @start.dup+a
+			else
+				@buffer += a
+			end
+		end
+		alias call top_down_fun
+
+		def end
+			@next.call @buffer
+			@next.end
+		end
+	end
+
+	class Each <Base
+		def each_fun *a
+			@exe.call *a
+		end
+		alias call each_fun
+
+		def end
+			nil
+		end
+		alias :clean :end
+	end
+
+	class P <Each
+		def initialize *a
+			super *a, &Kernel.method( :p)
+		end
+	end
+
+	class Inject <Base
+		attr_reader :it
+		alias :end :it
+
+		def initialize start, *a, &e
+			super *a, &e
+			@it = start
+		end
+
+		def inject_fun *a
+			@it = @exe.call @it, *a
+		end
+		alias call inject_fun
+	end
+
+	class To_a <Inject
+		def initialize *a, &e
+			super [], *a, &e
+		end
+	end
+
+	class Map <Collect
+		def map_fun *a
+			@exe.call *a, &@next
+		end
+		alias call map_fun
+	end
+
+	class Flatten <Base
+		def flatten_fun *a
+			a.each &@next.method( :call)
+		end
+		alias call flatten_fun
+	end
+
+	class Reduce <Base
+		def initialize iv = ::Functional::DEFAULT, *a, &exe
+			super *a, &exe
+			iv = Array.method :new  if ::Functional::DEFAULT == iv
+			@buf = if iv.kind_of?( ::Proc) || iv.kind_of?( ::Method)
+					Hash.new {|h,k| h[k] = iv.call }
+				else
+					{}.tap {|h| h.default = iv }
+				end
+		end
+
+		def reduce_fun k, *a
+			@buf[ k] = @exe.call k, @buf[ k], *a
+		end
+		alias call reduce_fun
+
+		def end
+			@buf.each &@next.method( :call)
+			@next.end
+		end
+	end
+
+	class ToHash <Base
+		def initialize
+			super
+			@buf = {}
+		end
+
+		def to_hash_fun k, *a
+			@buf[k] = a
+		end
+		alias call to_hash_fun
+
+		def end
+			@buf
+		end
+
+		def clean
+		end
+	end
+
+	class Slice <Base
+		def initialize n
+			@buf, @n = [], n
+		end
+
+		def slice_fun *a
+			@buf.push a
+			unless @n > @buf.size
+				@next.call @buf
+				@buf.clear
+			end
+		end
+		alias call slice_fun
+
+		def end
+			@next.call @buf
+			@next.end
+		end
+	end
+
+	class Cons <Base
+		def initialize n
+			@buf, @n = [], n
+		end
+
+		def cons_fun *a
+			@buf.push a
+		 	unless @n > @buf.size
+				class <<self
+					def call *a
+						@buf.push a
+						@next.call @buf
+						@buf.shift
+					end
+				end
+				@next.call @buf
+				@buf.shift
+			end
+		end
+		alias call cons_fun
+
+		def end
+			@next.call @buf  unless @n > @buf.size
+			@next.end
+		end
+	end
+
+	class Pager <Base
+		def initialize *opts
+			@pager = IO.popen ENV['PAGER'] || 'less', 'w'
+			opts.each do |opt|
+				case opt.to_s
+				when *%w[inspect i] then alias call call_inspect
+				else raise ArgumentError, "Unknown opt: #{opt}"
+				end
+			end
+		end
+
+		def call_inspect *a
+			@pager.puts a.inspect
+		end
+
+		def pager_fun *a
+			@pager.puts a
+		end
+		alias call pager_fun
+
+		def clean
+			@pager.close
+		end
+
+		def end
+			clean
+			nil
+		end
+	end
+
+	attr_accessor :next, :stack, :obj, :func, :args
+
+	def initialize obj = nil, func = nil, *args
+		@next, @stack, @obj, @func, @args = self, self, obj, func, args
+	end
+
+	def push a
+		@stack = @stack.next = a
 		self
 	end
 
-	def initialize obj = nil, func = nil, *args
-		@stack, @obj, @func, @args = [], obj, func, args
-	end
-
 	def collect &exe
-		push_method "value=%s(value)", &exe
+		push Collect.new( &exe)
 	end
 
-	# map/reduce?
 	def map &exe
-		raise "Reserved for MapReduce."
+		push Map.new( &exe)
 	end
 
-	# map/reduce?
+	def reduce iv = ::Functional::DEFAULT, &exe
-	def reduce &exe
+		push Reduce.new( iv, &exe)
-		raise "Reserved for MapReduce."
 	end
 
 	def select &exe
-		push_method "%s(value)||next", &exe
+		push Select.new( &exe)
 	end
 
-	def delete_if &exe
+	def grep re
-		push_method "%s(value)&&next", &exe
+		push Select.new( &re.method( :match))
+	end
+
+	def filter &exe
+		push Filter.new( &exe)
+	end
+	alias reject filter
+
+	def compact
+		push Compact.new
+	end
+
+	def updown init, &exe
+		push UpDown.new( init, &exe)
+	end
+
+	def topdown init, &exe
+		push TopDown.new( init, &exe)
+	end
+
+	def flatten &exe
+		push Flatten.new
 	end
 
 	def each &exe
 		return self  unless exe
-		@obj.send @func || :each, *@args, &eval( "lambda{|value|#{@stack.join( ";")};exe.call(value)}")
+		push Each.new( &exe)
+		run
+	end
+
+	def to_hash
+		push ToHash.new
+		run
+	end
+
+	def join deli
+		push Inject.new('') {|i,j|i+deli+j}
+		run
+	end
+
+	def run
+		@obj.send @func||:each, *@args, &@next #.method(:call)
+		@next.end
+	rescue Object
+		@next.clean
+		raise $!
+	end
+
+	def p
+		each &Kernel.method( :p)
+	end
+
+	def pager *opts
+		push Pager.new( *opts)
+		run
+	end
+
+	def sort &exe
+		to_a.sort &exe
+	end
+
+	def sort_by &exe
+		to_a.sort_by &exe
+	end
+
+	# [ _A, _B, ..., _C, ..., _D ] ==> [ [0, _A], [1, _B], ..., [_I, _C], ..., [_N, _D]]
+	# [ [_A|_As], [_B|_Bs], ..., [_C|_Cs], ..., [_D|_Ds] ] ==> [ [0,_A|_As], [1,_B|_Bs], ..., [_I,_C|_Cs], ..., [_N,_D|_Ds] ]
+	def with_index &exe
+		i = 0
+		exe ||= Array.method :[]
+		push Collect.new {|*a| exe.call i, *a; i += 1 }
+	end
+
+	def slice n, &exe
+		push Slice.new( n)
+		block_given? ? self.collect( &exe) : self
+	end
+
+	def cons n, &exe
+		push Cons.new( n)
+		block_given? ? self.collect( &exe) : self
+	end
+
+	def tap &exe
+		push Tap.new( &exe)
+	end
+
+	class Save < Base
+		attr_reader :db
+
+		def initialize db
+			@db = db
+		end
+
+		def call k, *v
+			@db[ k] = v.length == 1 ? v.first : v
+		end
+	end
+
+	def save db
+		push Save.new( db)
 	end
 end

test/functional_test.rb

@@ -0,0 +1,29 @@
+require 'test/unit'
+require 'functional'
+
+class FunTest < Test::Unit::TestCase
+	M = 0..100
+
+	def doit_fun m, &exe
+		f = m.to_fun
+		yield f
+		f.to_a
+	end
+
+	def test_to_fun_exists
+		assert_respond_to Object, :to_fun
+	end
+
+	def test_to_a
+		assert_equal M.to_a, doit_fun( M) {|x| x }
+	end
+
+	def test_collect
+		l = lambda {|x| x*2}
+		assert_equal M.collect( &l), doit_fun( M) {|x| x.collect( &l) }
+	end
+
+	def test_inject
+		assert_equal M.inject( 0) {|i,j| i+j }, M.to_fun.inject( 0) {|i,j| i+j }
+	end
+end