1Gtk2::Ex::FormFactory::URsuelresC(o3n)tributed Perl DocuGmtekn2t:a:tEixo:n:FormFactory::Rules(3)
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6 Gtk2::Ex::FormFactory::Rules - Rule checking in a FormFactory framework
7
9 Gtk2::Ex::FormFactory::Rules->new (
10 rules => Hashref of rules and their implemenation CODEREF's,
11 rules_messages => Hashref of the rules' error messages,
12 message_format => Format of the "Invalid rules" message thrown
13 on the GUI,
14 );
15
17 This class implements rule checking in a Gtk2::Ex::FormFactory
18 framework. Each widget can have on or more rules (combined with the
19 locical and operator, except for the special "or-empty" rule described
20 beyond) which are checked against the widget's value when the user
21 changes it. This way you can prevent the user from entering illegal
22 data at a high level.
23 Once the user entered illegal data, the old (legal) value is restored
25 and a corresponding error dialog pops up.
26
28 Gtk2::Ex::FormFactory::Rules
29
31 Attributes are handled through the common get_ATTR(), set_ATTR() style
32 accessors.
33 rules = HASHREF [optional]
35 This is a hash of user specified rules. A rule has a name (the hash
36 key) and a CODREF (the hash value) which implements the rule. The
37 CODEREF has the following prototype:
38 $error = &$CODEREF ($value)
40 If $value doesn't match the rule, $error is the corresponding error
42 message. $error is undef, if $value is Ok.
43 rules_messages = HASHREF [optional]
45 This is a hash of the error messages of the user specified rules.
46 A message should read read as follows:
47 {field} is an odd value.
49 When presented to the user, the {field} place holder is replaced
51 with the label of the widget in question.
52 message_format = SCALAR [optional]
54 This is the format string for the error message which is displayed
55 to the user. The default is:
56 Data entered is invalid.\n\n[MESSAGES]\nOld value restored.
58 where [MESSAGES] is replaced with the actual list of error
60 messages.
61
63 This is a verbatim snapshot of the builtin rules and rules_messages
64 hashes. Please take a look at Gtk2::Ex::FormFactory::Rules' source code
65 for a recent list of builtin rules:
66 my %RULES = (
68 "empty" => sub { $_[0] eq '' },
69 "not-empty" => sub { $_[0] ne '' },
70 "alphanumeric" => sub { $_[0] =~ /^\w+$/ },
72 "identifier" => sub { $_[0] =~ /^[a-z_]\w*$/i },
73 "no-whitespace" => sub { $_[0] !~ /\s/ },
74 "zero" => sub { $_[0] =~ /^0(\.0*)?$/ },
76 "not-zero" => sub { $_[0] !~ /^0(\.0*)?$/ },
77 "integer" => sub { $_[0] =~ /^[+-]?\d+$/ },
79 "positive-integer" => sub { $_[0] =~ /^[+]?\d+$/ },
80 "negative-integer" => sub { $_[0] =~ /^-\d+$/ },
81 "float" => sub { $_[0] =~ /^[+-]?\d+(\.\d+)?$/ },
83 "positive-float" => sub { $_[0] =~ /^\+?\d+(\.\d+)?$/ },
84 "negative-float" => sub { $_[0] =~ /^-\d+(\.\d+)?$/ },
85 "odd" => sub { $_[0] % 2 },
87 "even" => sub { !($_[0] % 2) },
88 "file-executable" => sub { (!-d $_[0] && -x $_[0]) },
90 "file-writable" => sub { (!-d $_[0] && -w $_[0]) },
91 "file-readable" => sub { (!-d $_[0] && -r $_[0]) },
92 "dir-writable" => sub { (-d $_[0] && -w $_[0]) },
94 "dir-readable" => sub { (-d $_[0] && -r $_[0]) },
95 "parent-dir-writable" => sub { -w dirname($_[0]) },
97 "parent-dir-readable" => sub { -r dirname($_[0]) },
98 "executable-command" => "_rule_result",
100 );
101 my %RULES_MESSAGES = (
103 "empty" => "{field} is not empty.",
104 "not-empty" => "{field} is empty.",
105 "alphanumeric" => "{field} is not alphanumeric.",
107 "identifier" => "{field} is no identifier.",
108 "no-whitespace" => "{field} contains whitespace.",
109 "zero" => "{field} is not zero",
111 "not-zero" => "{field} is zero",
112 "integer" => "{field} is no integer.",
114 "positive-integer" => "{field} is no positive integer.",
115 "negative-integer" => "{field} is no negative integer.",
116 "float" => "{field} is no float.",
118 "positive-float" => "{field} is no positive float.",
119 "negative-float" => "{field} is no negativ float.",
120 "odd" => "{field} is not odd.",
122 "even" => "{field} is not even.",
123 "file-executable" => "{field} is no file and/or not executable.",
125 "file-writable" => "{field} is no file and/or not writable.",
126 "file-readable" => "{field} is no file and/or not readable.",
127 "dir-writable" => "{field} is no directory and/or not writable.",
129 "dir-readable" => "{field} is no directory and/or not readable.",
130 "parent-dir-writable" => "{field} has no writable parent directory.",
132 "parent-dir-readable" => "{field} has no readable parent directory.",
133 );
134 Special "or-empty" rule
136 There is a special rule called "or-empty". If this rule occurs
137 everywhere in the list of rules and the actual value is empty, rule
138 checking quits immediately with a positive result, discarding error
139 states from earlier rules.
140 Example: [ "positive-integer", "or-empty" ]
142 All rules are combined with "and", which is usually sufficient, but
144 without this special "or-empty" case the common case optionally empty
145 fields can't be done.
146
148 Jörn Reder <joern at zyn dot de>
149
151 Copyright 2004-2006 by Jörn Reder.
152 This library is free software; you can redistribute it and/or modify it
154 under the terms of the GNU Library General Public License as published
155 by the Free Software Foundation; either version 2.1 of the License, or
156 (at your option) any later version.
157 This library is distributed in the hope that it will be useful, but
159 WITHOUT ANY WARRANTY; without even the implied warranty of
160 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
161 Library General Public License for more details.
162 You should have received a copy of the GNU Library General Public
164 License along with this library; if not, write to the Free Software
165 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307
166 USA.
167
169 Hey! The above document had some coding errors, which are explained
170 below:
171 Around line 349:
173 Non-ASCII character seen before =encoding in 'Jörn'. Assuming UTF-8
174perl v5.28.0 2006-02-27 Gtk2::Ex::FormFactory::Rules(3)