Yahoo! Markup Language Reference
Abstract
This guide provides syntax and examples for each tag in the Yahoo! Markup Language (YML). It is intended for software developers who are familiar with technologies such as HTML, JavaScript, PHP, and web services.
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For the latest information, see the Yahoo! Application Platform Release Notes.
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Introduction to YML
What is YML?
Similar in format to XML, Yahoo! Markup Language (YML) provides functionality to Open Applications in a safe and standardized fashion. You include YML tags in the HTML code of an Open Application. At runtime, YAP processes YML tags and converts them into HTML. If necessary, JavaScript libraries on the end-points attach dynamic behaviors in the user's browser.
Benefits
YML offers the following benefits:
- Social data: YML tags make it easy for you to create applications that access social data, such as a list of the user's friends.
- Dynamic and secure interactions: Several YML tags provide UI widgets and and rich interactions that normally require untrusted JavaScript.
- Data encapsulation: YML tags allow sensitive and timely data to be presented to end-users in a uniform manner. The YML interpreter will replace tags with data only if the viewer has the proper access.
Syntax Rules
YML tags must conform to the following rules:
-
YML tags are namespaced with
yml:. However, since YML documents are not actually XML, no formal namespace declaration is required. -
All attributes must be enclosed in double quotes.
To specify double quotes within an attribute value,
enter the
"character reference. - If the data type of an attribute is boolean, allowed values are "true" and "false", which must be enclosed in double quotes.
-
Singleton tags (that is, tags with no closing tags) must end with
/>. - White space and indentations are passed through, but ignored in the interpretation phase.
- YML tags accept and produce characters in UTF-8 only.
YML Lite
YML Lite is a subset of YML designed for improved performance. The Small view of an Open Application can contain only HTML or YML Lite tags, which are: