1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
|
require "rexml/child"
module REXML
# A parent has children, and has methods for accessing them. The Parent
# class is never encountered except as the superclass for some other
# object.
class Parent < Child
include Enumerable
# Constructor
# @param parent if supplied, will be set as the parent of this object
def initialize parent=nil
super(parent)
@children = []
end
def add( object )
object.parent = self
@children << object
object
end
alias :push :add
alias :<< :push
def unshift( object )
object.parent = self
@children.unshift object
end
def delete( object )
found = false
@children.delete_if {|c| c.equal?(object) and found = true }
object.parent = nil if found
found ? object : nil
end
def each(&block)
@children.each(&block)
end
def delete_if( &block )
@children.delete_if(&block)
end
def delete_at( index )
@children.delete_at index
end
def each_index( &block )
@children.each_index(&block)
end
# Fetches a child at a given index
# @param index the Integer index of the child to fetch
def []( index )
@children[index]
end
alias :each_child :each
# Set an index entry. See Array.[]=
# @param index the index of the element to set
# @param opt either the object to set, or an Integer length
# @param child if opt is an Integer, this is the child to set
# @return the parent (self)
def []=( *args )
args[-1].parent = self
@children[*args[0..-2]] = args[-1]
end
# Inserts an child before another child
# @param child1 this is either an xpath or an Element. If an Element,
# child2 will be inserted before child1 in the child list of the parent.
# If an xpath, child2 will be inserted before the first child to match
# the xpath.
# @param child2 the child to insert
# @return the parent (self)
def insert_before( child1, child2 )
if child1.kind_of? String
child1 = XPath.first( self, child1 )
child1.parent.insert_before child1, child2
else
ind = index(child1)
child2.parent.delete(child2) if child2.parent
@children[ind,0] = child2
child2.parent = self
end
self
end
# Inserts an child after another child
# @param child1 this is either an xpath or an Element. If an Element,
# child2 will be inserted after child1 in the child list of the parent.
# If an xpath, child2 will be inserted after the first child to match
# the xpath.
# @param child2 the child to insert
# @return the parent (self)
def insert_after( child1, child2 )
if child1.kind_of? String
child1 = XPath.first( self, child1 )
child1.parent.insert_after child1, child2
else
ind = index(child1)+1
child2.parent.delete(child2) if child2.parent
@children[ind,0] = child2
child2.parent = self
end
self
end
def to_a
@children.dup
end
# Fetches the index of a given child
# @param child the child to get the index of
# @return the index of the child, or nil if the object is not a child
# of this parent.
def index( child )
count = -1
@children.find { |i| count += 1 ; i.hash == child.hash }
count
end
# @return the number of children of this parent
def size
@children.size
end
alias :length :size
# Replaces one child with another, making sure the nodelist is correct
# @param to_replace the child to replace (must be a Child)
# @param replacement the child to insert into the nodelist (must be a
# Child)
def replace_child( to_replace, replacement )
@children.map! {|c| c.equal?( to_replace ) ? replacement : c }
to_replace.parent = nil
replacement.parent = self
end
# Deeply clones this object. This creates a complete duplicate of this
# Parent, including all descendants.
def deep_clone
cl = clone()
each do |child|
if child.kind_of? Parent
cl << child.deep_clone
else
cl << child.clone
end
end
cl
end
alias :children :to_a
def parent?
true
end
end
end
|
