Page History

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Page map is a part of Session. Basically it is used as an interface for storing pages and their versions. Page map stores instances of pages (including component tree) which were visited by user during the current session. So every time user goes to another page or changes page state, the page instance is stored in a page map. There can be one or more page maps in one http session where each page map corresponds to a browser tab. Page maps are identified by their names.

In a sense, page maps can be viewed as an implementation detail of Session, since they are used only through IPageMap interface and some of their the functionality should be accessed only through Session.

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