DEFLABEL.html -- ACL2 Version 6.3

## DEFLABEL

build a landmark and/or add a documentation topic

    Major Section:  EVENTS

    Examples:
    (deflabel interp-section
       :doc
       ":Doc-Section ...")

    General Form:
    (deflabel name :doc doc-string)

where `name` is a new symbolic name (see name) and `doc-string` is an optional documentation string (see doc-string). This event adds the documentation string for symbol `name` to the `:``doc` database. By virtue of the fact that `deflabel` is an event, it also marks the current history with the `name`. Thus, even undocumented labels are convenient as landmarks in a proof development. For example, you may wish to undo back through some label or compute a theory expression (see theories) in terms of some labels. `Deflabel` events are never considered redundant. See redundant-events.

See defdoc for a means of attaching a documentation string to a name without marking the current history with that name.