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
|
<?xml version="1.0" encoding="utf-8"?>
<!-- $Revision$ -->
<sect1 xml:id="control-structures.continue" xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink">
<title>continue</title>
<?phpdoc print-version-for="continue"?>
<simpara>
<literal>continue</literal> is used within looping structures to
skip the rest of the current loop iteration and continue execution
at the condition evaluation and then the beginning of the next iteration.
</simpara>
<note>
<simpara>
In PHP the
<link linkend="control-structures.switch">switch</link> statement is
considered a looping structure for the purposes of
<literal>continue</literal>. <literal>continue</literal> behaves like
<literal>break</literal> (when no arguments are passed) but will
raise a warning as this is likely to be a mistake. If a
<literal>switch</literal> is inside a loop,
<literal>continue 2</literal> will continue with the next iteration
of the outer loop.
</simpara>
</note>
<simpara>
<literal>continue</literal> accepts an optional numeric argument
which tells it how many levels of enclosing loops it should skip
to the end of. The default value is <literal>1</literal>, thus skipping
to the end of the current loop.
</simpara>
<para>
<informalexample>
<programlisting role="php">
<![CDATA[
<?php
$arr = ['zero', 'one', 'two', 'three', 'four', 'five', 'six'];
foreach ($arr as $key => $value) {
if (0 === ($key % 2)) { // skip members with even key
continue;
}
echo $value . "\n";
}
?>
]]>
</programlisting>
&examples.outputs;
<screen>
<![CDATA[
one
three
five
]]>
</screen>
<programlisting role="php">
<![CDATA[
<?php
$i = 0;
while ($i++ < 5) {
echo "Outer\n";
while (1) {
echo "Middle\n";
while (1) {
echo "Inner\n";
continue 3;
}
echo "This never gets output.\n";
}
echo "Neither does this.\n";
}
?>
]]>
</programlisting>
&examples.outputs;
<screen>
<![CDATA[
Outer
Middle
Inner
Outer
Middle
Inner
Outer
Middle
Inner
Outer
Middle
Inner
Outer
Middle
Inner
]]>
</screen>
</informalexample>
</para>
<para>
Omitting the semicolon after <literal>continue</literal> can lead to
confusion. Here's an example of what you shouldn't do.
</para>
<para>
<informalexample>
<programlisting role="php">
<![CDATA[
<?php
for ($i = 0; $i < 5; ++$i) {
if ($i == 2)
continue
print "$i\n";
}
?>
]]>
</programlisting>
<para>
One can expect the result to be:
</para>
<screen>
<![CDATA[
0
1
3
4
]]>
</screen>
</informalexample>
</para>
<para>
<table>
<title>Changelog for <literal>continue</literal></title>
<tgroup cols="2">
<thead>
<row>
<entry>&Version;</entry>
<entry>&Description;</entry>
</row>
</thead>
<tbody>
<row>
<entry>7.3.0</entry>
<entry>
<literal>continue</literal> within a <literal>switch</literal> that is attempting to act like a <literal>break</literal> statement for the
<literal>switch</literal> will trigger an <constant>E_WARNING</constant>.
</entry>
</row>
</tbody>
</tgroup>
</table>
</para>
</sect1>
<!-- Keep this comment at the end of the file
Local variables:
mode: sgml
sgml-omittag:t
sgml-shorttag:t
sgml-minimize-attributes:nil
sgml-always-quote-attributes:t
sgml-indent-step:1
sgml-indent-data:t
indent-tabs-mode:nil
sgml-parent-document:nil
sgml-default-dtd-file:"~/.phpdoc/manual.ced"
sgml-exposed-tags:nil
sgml-local-catalogs:nil
sgml-local-ecat-files:nil
End:
vim600: syn=xml fen fdm=syntax fdl=2 si
vim: et tw=78 syn=sgml
vi: ts=1 sw=1
-->
|
