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
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
|
<?xml version="1.0" encoding="utf-8" ?>
<!DOCTYPE erlref SYSTEM "erlref.dtd">
<erlref>
<header>
<copyright>
<year>2000</year><year>2018</year>
<holder>Ericsson AB. All Rights Reserved.</holder>
</copyright>
<legalnotice>
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
</legalnotice>
<title>sets</title>
<prepared>Robert Virding</prepared>
<responsible>Bjarne Däcker</responsible>
<docno>1</docno>
<approved>Bjarne Däcker</approved>
<checked></checked>
<date>1999-07-27</date>
<rev>A</rev>
<file>sets.xml</file>
</header>
<module>sets</module>
<modulesummary>Functions for set manipulation.</modulesummary>
<description>
<p>Sets are collections of elements with no duplicate elements.
The representation of a set is undefined.</p>
<p>This module provides the same interface as the
<seealso marker="ordsets"><c>ordsets(3)</c></seealso> module
but with an undefined representation. One difference is
that while this module considers two elements as different if they
do not match (<c>=:=</c>), <c>ordsets</c> considers two elements as
different if and only if they do not compare equal (<c>==</c>).</p>
</description>
<datatypes>
<datatype>
<name name="set" n_vars="1"/>
<desc><p>As returned by
<seealso marker="#new/0"><c>new/0</c></seealso>.</p></desc>
</datatype>
<datatype>
<name name="set" n_vars="0"/>
</datatype>
</datatypes>
<funcs>
<func>
<name name="add_element" arity="2"/>
<fsummary>Add an element to a <c>Set</c>.</fsummary>
<desc>
<p>Returns a new set formed from <c><anno>Set1</anno></c> with
<c><anno>Element</anno></c> inserted.</p>
</desc>
</func>
<func>
<name name="del_element" arity="2"/>
<fsummary>Remove an element from a <c>Set</c>.</fsummary>
<desc>
<p>Returns <c><anno>Set1</anno></c>, but with
<c><anno>Element</anno></c> removed.</p>
</desc>
</func>
<func>
<name name="filter" arity="2"/>
<fsummary>Filter set elements.</fsummary>
<desc>
<p>Filters elements in <c><anno>Set1</anno></c> with boolean function
<c><anno>Pred</anno></c>.</p>
</desc>
</func>
<func>
<name name="fold" arity="3"/>
<fsummary>Fold over set elements.</fsummary>
<desc>
<p>Folds <c><anno>Function</anno></c> over every element in
<c><anno>Set</anno></c> and returns the final value of the
accumulator. The evaluation order is undefined.</p>
</desc>
</func>
<func>
<name name="from_list" arity="1"/>
<fsummary>Convert a list into a <c>Set</c>.</fsummary>
<desc>
<p>Returns a set of the elements in <c><anno>List</anno></c>.</p>
</desc>
</func>
<func>
<name name="intersection" arity="1"/>
<fsummary>Return the intersection of a list of <c>Sets</c>.</fsummary>
<desc>
<p>Returns the intersection of the non-empty list of sets.</p>
</desc>
</func>
<func>
<name name="intersection" arity="2"/>
<fsummary>Return the intersection of two <c>Sets</c>.</fsummary>
<desc>
<p>Returns the intersection of <c><anno>Set1</anno></c> and
<c><anno>Set2</anno></c>.</p>
</desc>
</func>
<func>
<name name="is_disjoint" arity="2"/>
<fsummary>Check whether two <c>Sets</c> are disjoint.</fsummary>
<desc>
<p>Returns <c>true</c> if <c><anno>Set1</anno></c> and
<c><anno>Set2</anno></c> are disjoint (have no elements in common),
otherwise <c>false</c>.</p>
</desc>
</func>
<func>
<name name="is_element" arity="2"/>
<fsummary>Test for membership of a <c>Set</c>.</fsummary>
<desc>
<p>Returns <c>true</c> if <c><anno>Element</anno></c> is an element of
<c><anno>Set</anno></c>, otherwise <c>false</c>.</p>
</desc>
</func>
<func>
<name name="is_empty" arity="1" since="OTP 21.0"/>
<fsummary>Test for empty set.</fsummary>
<desc>
<p>Returns <c>true</c> if <c><anno>Set</anno></c> is an empty set,
otherwise <c>false</c>.</p>
</desc>
</func>
<func>
<name name="is_set" arity="1"/>
<fsummary>Test for a <c>Set</c>.</fsummary>
<desc>
<p>Returns <c>true</c> if <c><anno>Set</anno></c> is a set of
elements, otherwise <c>false</c>.</p>
</desc>
</func>
<func>
<name name="is_subset" arity="2"/>
<fsummary>Test for subset.</fsummary>
<desc>
<p>Returns <c>true</c> when every element of <c><anno>Set1</anno></c> is
also a member of <c><anno>Set2</anno></c>, otherwise <c>false</c>.</p>
</desc>
</func>
<func>
<name name="new" arity="0"/>
<fsummary>Return an empty set.</fsummary>
<desc>
<p>Returns a new empty set.</p>
</desc>
</func>
<func>
<name name="size" arity="1"/>
<fsummary>Return the number of elements in a set.</fsummary>
<desc>
<p>Returns the number of elements in <c><anno>Set</anno></c>.</p>
</desc>
</func>
<func>
<name name="subtract" arity="2"/>
<fsummary>Return the difference of two <c>Sets</c>.</fsummary>
<desc>
<p>Returns only the elements of <c><anno>Set1</anno></c> that are not
also elements of <c><anno>Set2</anno></c>.</p>
</desc>
</func>
<func>
<name name="to_list" arity="1"/>
<fsummary>Convert a <c>Set</c>into a list.</fsummary>
<desc>
<p>Returns the elements of <c><anno>Set</anno></c> as a list.
The order of the returned elements is undefined.</p>
</desc>
</func>
<func>
<name name="union" arity="1"/>
<fsummary>Return the union of a list of <c>Sets</c>.</fsummary>
<desc>
<p>Returns the merged (union) set of the list of sets.</p>
</desc>
</func>
<func>
<name name="union" arity="2"/>
<fsummary>Return the union of two <c>Sets</c>.</fsummary>
<desc>
<p>Returns the merged (union) set of <c><anno>Set1</anno></c> and
<c><anno>Set2</anno></c>.</p>
</desc>
</func>
</funcs>
<section>
<title>See Also</title>
<p><seealso marker="gb_sets"><c>gb_sets(3)</c></seealso>,
<seealso marker="ordsets"><c>ordsets(3)</c></seealso></p>
</section>
</erlref>
|