document atom and predicate completion with TAB

This feature, added via
https://github.com/mthom/scryer-prolog/pull/1467, makes the toplevel
interaction a lot more convenient in many cases.

Many thanks to @euanlacy!

diff --git a/README.md b/README.md
index 7f3faa71035e3a1cf31566582442499611f5160f..68fab560ed92bc4d1b112280dd57aab388883efe 100644 (file)
--- a/README.md
+++ b/README.md
@@ -205,6 +205,11 @@ or `.` to abort the search and return to the
 toplevel prompt. Press `f` to see the next 5 answers, and
 `a` to see all answers. Press `h` to show a help message.
 
+Use `TAB` to complete atoms and predicate names in queries. For
+instance, after consulting the program above, typing `decl` followed
+by `TAB` yields `declarative_world`. Press `TAB` repeatedly
+to cycle through alternative completions.
+
 To quit Scryer Prolog, use the standard predicate `halt/0`:
 
 ```