The Storyspace Guard Field The distinctive feature of Storyspace is its dynamic link, a unidirectional link that can be activated or deactivated by a guard field. The guard field is a simply boolean expression whose terms may include the word clicked or the names of previously-visited notes enclosed in quotation marks.
The guard field
(“A” & (!”B”)) | Anne
is satisfied if the reader has read the note “A” but not the note “B”, or if the reader has clicked on the word “Anne”. Guard fields proved invaluable for breaking cycles, a central anxiety of early hypertext research,
The underlying mechanism, which simply disables unwanted links, is easy for new writers to understand.
Storyspace 3 Mark Bernstein Eastgate Systems, Inc.