Though the principal predicates for invoking behaviour are send/2 and get/3, XPCE provides an alternative using send/[2-12] and get/[3-13]. The following goals are all identical.
| send(Box, width(100)) | send(Box, width, 100) |
| get(Point, distance(point(10,10), D) | get(Point, distance, point(10,1), D) |
This alternative is provided for compatibility to pre-5.0 versions as well as to support users that dislike the new-style send/2 and get/3. It is realised using goal_expansion/2 and thus poses only a small compile-time overhead.