Common attributes parser code module, for use by Plugins authors.

Summary of Contents

Provides a simple and consistent interface for creation and management of lists of standard TWiki-syntax attribute value lists, as used in tags.

Detailed Documentation

Package TWiki::Contrib::Attrs

Class of attribute sets, designed for parsing and storing attribute values from a TWiki tag e.g. %TAG{fred="bad" "sad" joe="mad"}%

An attribute set is a map containing an entry for each parameter. The default parameter (unnamed quoted string) is named __default__ in the map. Attributes declared later in the string will override those of the same name defined earlier. Escaping quotes is not supported.

The parser is forgiving; it will handle standard TWiki syntax (parameter values double-quoted) but also single-quoted values, unquoted spaceless values, spaces around the =, and commas as well as spaces separating values.

new ($string) => Attrs object ref

$string

String containing attribute specification

Parse a standard attribute string containing name=value pairs and create a new attributes object. The value may be a word or a quoted string. If there is an error during parsing, the parse will complete but $this->{__error__} will be set in the new object.

Example:

use TWiki::Contrib::Attrs;
my $attrs = new TWiki::Contrib::Attrs('the="time has come", "the walrus" said to=speak of='many things');

In this example:

• the will be time has come
• __default__ will be the walrus
• said will be on
• to will be speak
• of will be many things

get( $key) => value

$key	Attribute name

Get an attr value; return undef if not set

isEmpty() => boolean

Return false if attribute set is not empty.

remove($key) => value

$key	Attribute to remove

Remove an attr value from the map, return old value. After a call to remove the attribute is no longer defined.

toString() => string

Generate a printed form for the map, using standard attribute syntax, with only the single-quote extension syntax observed (no {} brackets, though).

Settings

• Name of the perl package
  • Set STUB = TWiki::Contrib::Attrs

Installation Instructions

• Download the ZIP file from the Plugin web (see below)
• Unzip AttrsContrib.zip in your twiki installation directory. Content:

  File:	Description:
  data/TWiki/AttrsContrib.txt
  lib/TWiki/Contrib/Attrs.pm
  lib/TWiki/Contrib/AttrsContrib/build.pl
  lib/TWiki/Contrib/AttrsContrib/test.zip

Plugin Info

Author:	TWiki:Main/CrawfordCurrie http://www.c-dot.co.uk
Copyright ©:	2001, Motorola Corp, All Rights Reserved
License:	GPL
Dependencies:	None
Change History:
14/08/04	Separated out from SharedCode module
Home:	http://TWiki.org/cgi-bin/view/Plugins/AttrsContrib
Feedback:	http://TWiki.org/cgi-bin/view/Plugins/AttrsContribDev

Related Topics: TWikiPreferences

-- TWiki:Main/CrawfordCurrie - 12:53:50 16 August 2004