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103 строки
2.0 KiB
Plaintext
103 строки
2.0 KiB
Plaintext
.\" enumerator.txt - -*- Indented-Text -*-
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$Idaemons: /home/cvs/rb/enumerator/enumerator.txt,v 1.2 2001/07/15 10:19:24 knu Exp $
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$RoughId: enumerator.txt,v 1.5 2003/02/20 12:24:51 knu Exp $
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$Id$
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** Enumerable::Enumerator(Class)
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A class which provides a method `each' to be used as an Enumerable
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object.
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Superclass: Object
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Mix-ins: Enumerable
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require 'enumerator'
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Class Methods:
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new(obj, method = :each, *args)
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Creates a new Enumerable::Enumerator object, which is to be
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used as an Enumerable object using the given object's given
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method with the given arguments.
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e.g.:
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str = "xyz"
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enum = Enumerable::Enumerator.new(str, :each_byte)
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a = enum.map {|b| '%02x' % b } #=> ["78", "79", "7a"]
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Methods:
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each {...}
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Iterates the given block using the object and the method
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specified in the first place.
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Requiring this module also adds some methods to the Object class:
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to_enum(method = :each, *args)
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enum_for(method = :each, *args)
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Returns Enumerable::Enumerator.new(self, method, *args).
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e.g.:
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str = "xyz"
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enum = str.enum_for(:each_byte)
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a = enum.map {|b| '%02x' % b } #=> ["78", "79", "7a"]
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# protects an array from being modified
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a = [1, 2, 3]
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some_method(a.to_enum)
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And the Enumerable module.
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each_slice(n) {...}
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Iterates the given block for each slice of <n> elements.
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e.g.:
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(1..10).each_slice(3) {|a| p a}
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# outputs below
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[1, 2, 3]
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[4, 5, 6]
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[7, 8, 9]
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[10]
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enum_slice(n)
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Returns Enumerable::Enumerator.new(self, :each_slice, n).
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each_cons(n) {...}
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Iterates the given block for each array of consecutive <n>
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elements.
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e.g.:
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(1..10).each_cons(3) {|a| p a}
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# outputs below
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[1, 2, 3]
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[2, 3, 4]
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[3, 4, 5]
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[4, 5, 6]
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[5, 6, 7]
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[6, 7, 8]
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[7, 8, 9]
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[8, 9, 10]
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enum_cons(n)
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Returns Enumerable::Enumerator.new(self, :each_cons, n).
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enum_with_index
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Returns Enumerable::Enumerator.new(self, :each_with_index).
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-------------------------------------------------------
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Local variables:
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fill-column: 70
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end:
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