The transition Command


transition [[element] <transition target>]
  {<property name> [from <string>} to <string>}
[over <time expression> | using <expression>]


The transition command allows you to transition properties on an element from one value to another.

If you use the form transition <transition target> the transition will take place on the specified target, otherwise it is done on the current me.

The transition target can be a pseudo-possessive:

  transition my opacity to 0
  transition the div's opacity to 0
  transition #anotherDiv's opacity to 0
  transition .aClass's opacity to 0

If the target is a symbol it will need to be preceded by a the or the keyword element to distinguish the symbol from a property name:

  transition element foo's opacity to 0

Following the start is a series of transitions, starting with a style property name, followed optionally by a from and an initial value. If this is omitted, the current calculated value of the property is used.

Next comes a required to followed by a final value to transition the property too. Note that you can use either strings or naked strings.

You can optionally set the transition time by using the over clause and passing in a time expression such as 500ms or 2 seconds.

Finally, if you don't specify a transition time, you can optionally set the transition style by using the using clause and passing in a string that specifies a transformation specification, e.g. all 1s ease-in.

By default, hyperscript will use the value specified in _hyperscript.config.defaultTransition, which is set to all 500ms ease-in. You may update this property to change the default.

The transition command provides a special value, initial that can be used. When a transition first occurs on an element it will snapshot the original value of that style property and keep it for future reference via the initial keyword.

Note that this command is asynchronous and will block until the transition ends.


<div _="on click transition my opacity to 0 then remove me">
  Fade then remove me