Similar to my <<replace>> macro, this code causes the passage text in between the <<timedreplace>> and <<becomes>> tags to be replaced with what is between those and the <<endtimedreplace>> tag, after a certain amount of time has elapsed.

Variants
* <<timedinsert>> causes its text to be inserted into the page. It doesn't need a <<becomes>> tag to function.
* <<timedremove>> works in a matching fashion, removing its contained text after the time elapses.
* <<timedcontinue>> is similar to <<timedinsert>> but does not require a final <<endtimedcontinue>> - instead, it causes all subsequent text in the passage to appear.
Gains
You can also substitute the <<becomes>> tag with <<gains>> to cause the next run of text to appear at the end of the previous run, without replacing it.
Chains
If you put multiple <<becomes>> or <<gains>> tags in, the macro will make them appear as well after the same amount of time passes.

Install my <<Replace>> Macro Set to use these macros.

This takes CSS time values, which are decimal numbers ending in "s" (for seconds) or "ms" (for milliseconds).

Usage examples:
* <<timedreplace 2s >>You see nothing. <<becomes>>After 2 seconds, you still see nothing.<<endtimedreplace>>
* <<timedreplace 2s >>You see <<gains>>a dog, <<gains>>a walrus, <<gains>>and a civet.<<endtimedreplace>>
* You search. <<timedinsert 1s>>You find nothing.<<endtimedinsert>>.
* <<timedremove 2.5s >>Something is disappearing... <<endtimedremove>>
* Look <<timedcontinue 3s>>A bird just few by...

Example program.

Implementation details:

* If inserted text appears and descends below the bottom of the screen, the page should automatically scroll down to make it visible.
* Note: due to the way the browser and Twine interact, any changes made by code inside a <<timedreplace>> tag will be forgotten if you use the Back or Forward browser buttons, unless you use this script.

Version history:
* 16/06/2013 - Updated regarding Combined Replace Macro Set.
* 26/04/2013 - Added timedcontinue.
* 05/04/2013 - Added timedinsert and timedremove, as well as downward scrolling.
* 07/03/2013 - Made the transition CSS-based.
* 01/02/2013 - Initial.
_{Feel free to report any bugs to @webbedspace.}