Most of Unpoly's features share one shape: the common case is an HTML attribute, the same feature is also available as a JavaScript function, and its defaults can be changed through a global configuration. Learn the pattern once, and every feature in the reference will look familiar.
The quickest way is an attribute in your HTML. This link swaps the main fragment with an animated transition:
<a href="/path" up-follow up-transition="cross-fade">Click me</a> <!-- mark: up-transition="cross-fade" -->
The same feature exists as a JavaScript function, for when your own code triggers the behavior. Attributes become camel-cased options:
up.follow(link, { transition: 'cross-fade' }) // mark: transition
When your whole app should behave that way, set a configuration default instead of repeating the attribute:
up.fragment.config.navigateOptions.transition = 'cross-fade'
All three set the same option. They differ in scope: one element, one call, or every navigation in your app.
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