help/[0,1] hookable,development



Gives basic information, such as how to start using the help system and how to exit from Prolog.


Displays help available on Topic.


Topic atom


help(Topic) is the basic help command. It attempts to accept any argument you give it as a topic for which help may exist in the manual. The argument is converted into a character string, and all the index entries that start with that string are combined into a menu, which gives you a choice of entry points into the manual hierarchy.

It is not necessary to type the whole of the word that is the topic you want information about. However, the fewer characters you type, the larger the menu is likely to be, because more index entries will contain with that character sequence.

A hook is provided so that users can add to or replace this information: help/0 first calls user_help/0, and if that succeeds help/0 does nothing else. Only if the call to user_help/0 fails is the standard information displayed.

With the emacs interface see ema-emi

With QUI see qui-mai

This predicate is not supported in runtime systems.

See Also

user_help/0, manual/[0,1]