listing/0

Write all existing program clauses, in a form readable by humans

listing (without arguments) writes the entire set of all existing program clauses, to the screen (or current output device).

Compatibility: LPA Win-Prolog, Swindon Prolog, nearly all other Prologs.

Example: The following:

tell("File.Dba"),listing,told

is functionally identical to:

save("File.Dba")

See also:

listing/1

listing/2

Historical Remark:

This predicate was originally "list" inside the P.I.E. inference engine (which is also the basis for G.I.S. Prolog). However, most other Prologs use "listing" instead, and -furthermore- 'list/1' is a standard predicate doing something completely different, inside LPA Win-Prolog and in many other Prologs. For all these reasons, the original "list" predicate was replaced by "listing" in G.I.S. Prolog.