9.1 Interacting with the Top-level

When you start a new top-level, it prompts you to enter a Prolog query by displaying the query prompt, which is usually ‘?- ’. You post your query by typing it at the prompt, and pressing RET (comint-send-input) to send it. If the query succeeds with a choicepoint, the top-level lets you to perform one of several actions by typing a single character, such as ; to get the next answer. Sweep Top-level mode detects that the top-level expects a single character input, and sends the character you type to the top-level immediately. After the top-level is done with answering your query, it prompts you again to post a new one.

The Sweep top-level provides input completion at the query prompt, which works similarly to the in-buffer completion you get in Sweep Prolog mode buffers (see Code Completion). Namely, to complete a partial predicate name or other input in the top-level prompt, type C-M-i (or M-TAB).