API Reference

The following is a list of all user-facing parts of Temperance.

If there are backwards-incompatible changes to anything listed here, they will be noted in the changelog and the author will feel bad.

Anything not listed here is subject to change at any time with no warning, so don't touch it.

Package TEMPERANCE

*STANDARD-DATABASE* (variable)

The standard database used when t is supplied as a database designator.

FACT (macro)

(FACT DATABASE FACT)

Add a logical fact to database.

fact will be wrapped in (quote ...). If you need to dynamically construct facts at runtime, see invoke-fact.

Examples:

(fact t (likes kim cats))
(fact t (likes sjl cats))

FACTS (macro)

(FACTS DATABASE
  &BODY
  FACTS)

Add zero or more logical facts to database.

Each fact in facts will be wrapped in (quote ...). If you need to dynamically construct facts at runtime, see invoke-facts.

Examples:

(facts t
  (successor 0 1)
  (successor 1 2)
  (successor 2 3))

FINALIZE-LOGIC-FRAME (function)

(FINALIZE-LOGIC-FRAME DATABASE)

Finalize the top logic frame of database's logic stack.

An error will be signaled if the logic stack is empty or the top frame is already finalized.

INVOKE-FACT (function)

(INVOKE-FACT DATABASE FACT)

Add a logical fact to database.

The fact macro is a nicer interface, but this function can be useful if you need to build rules dynamically at runtime.

Examples:

(invoke-fact t '(successor 0 1))

(defun add-cat-lover (name)
  (invoke-fact t `(likes ,name cats)))

INVOKE-FACTS (function)

(INVOKE-FACTS DATABASE &REST FACTS)

Add zero or more logical facts to database.

The facts macro is a nicer interface, but this function can be useful if you need to build rules dynamically at runtime.

Examples:

(invoke-facts t
              '(successor 0 1)
              '(successor 1 2)
              '(successor 2 3))

INVOKE-PROVE (function)

(INVOKE-PROVE DATABASE &REST TERMS)

INVOKE-QUERY (function)

(INVOKE-QUERY DATABASE &REST TERMS)

INVOKE-QUERY-ALL (function)

(INVOKE-QUERY-ALL DATABASE &REST TERMS)

INVOKE-QUERY-DO (function)

(INVOKE-QUERY-DO DATABASE FUNCTION &REST TERMS)

INVOKE-QUERY-FIND (function)

(INVOKE-QUERY-FIND DATABASE PREDICATE &REST TERMS)

INVOKE-QUERY-FOR (function)

(INVOKE-QUERY-FOR DATABASE VARIABLE &REST TERMS)

INVOKE-QUERY-MAP (function)

(INVOKE-QUERY-MAP DATABASE FUNCTION &REST TERMS)

INVOKE-RULE (function)

(INVOKE-RULE DATABASE HEAD &REST BODY)

Add a logical rule to database with the given head and body.

The rule macro is a nicer interface, but this function can be useful if you need to build rules dynamically at runtime.

Example:

; Sally like anyone who likes cats
(invoke-rule t '(likes sally ?who)
  '(likes ?who cats))

MAKE-DATABASE (function)

(MAKE-DATABASE)

Create and return a fresh database.

POP-LOGIC-FRAME (function)

(POP-LOGIC-FRAME DATABASE)

Pop off the top logic frame of database's logic stack.

An error will be signaled if the logic stack is empty or the top frame is unfinalized.

PROVE (macro)

(PROVE DATABASE &REST TERMS)

PUSH-LOGIC-FRAME (function)

(PUSH-LOGIC-FRAME DATABASE)

Push a new, open logic frame onto database.

An error will be signaled if there is already an unfinalized logic frame on the top of the stack.

PUSH-LOGIC-FRAME-WITH (macro)

(PUSH-LOGIC-FRAME-WITH DATABASE
  &BODY
  BODY)

Push a new logic frame onto database, run body, and finalize it.

This is a convenience macro for the common process of pushing a logic frame, adding some stuff to it, and finalizing it right away.

Example:

(push-logic-frame-with t
  (rule t (likes sally ?who)
    (likes ?who cats))
  (facts t
    (likes kim cats)
    (likes sjl cats)
    (likes bob dogs)))

(query-all t (likes sally ?who))
; =>
((?who kim) (?who sjl))

QUERY (macro)

(QUERY DATABASE &REST TERMS)

QUERY-ALL (macro)

(QUERY-ALL DATABASE &REST TERMS)

QUERY-DO (macro)

(QUERY-DO DATABASE FUNCTION &REST TERMS)

QUERY-FIND (macro)

(QUERY-FIND DATABASE PREDICATE &REST TERMS)

QUERY-FOR (macro)

(QUERY-FOR DATABASE VARIABLE &REST TERMS)

QUERY-MAP (macro)

(QUERY-MAP DATABASE FUNCTION &REST TERMS)

RESET-STANDARD-DATABASE (function)

(RESET-STANDARD-DATABASE)

Reset *standard-database* to a new, fresh database.

RULE (macro)

(RULE DATABASE
    HEAD
  &BODY
  BODY)

Add a logical rule to database with the given head and body.

head and body will be wrapped in (quote ...). If you need to dynamically construct rules at runtime, see invoke-rule.

Example:

; Sally like anyone who likes cats
(rule t (likes sally ?who)
  (likes ?who cats))

WITH-DATABASE (macro)

(WITH-DATABASE DATABASE
  &BODY
  BODY)

Execute body with *standard-database* bound to database.

WITH-FRESH-DATABASE (macro)

(WITH-FRESH-DATABASE
  &BODY
  BODY)

Execute body with *standard-database* bound to a new, fresh database.