CLIPS Language: Historic On-Line Help

 CONSTRUCT_SUMMARY

This section gives a general overview of the available CLIPS constructs.

Subtopics:
DEFRULE                    DEFCLASS
DEFFACTS                   DEFINSTANCES
DEFTEMPLATE                DEFMESSAGE-HANDLER
DEFGLOBAL                  DEFMODULE
DEFFUNCTION                CONSTRAINT_ATTRIBUTES            
DEFGENERIC/DEFMETHOD

END-ENTRY 

DEFRULE

 CONSTRUCT_SUMMARY
  DEFRULE

One of the primary methods of representing knowledge in CLIPS is a rule.  
A rule is a collection of conditions and the actions to be taken if the 
conditions are met.  The developer of an expert system defines the rules 
which describe how to solve a problem.  Rules execute (or fire) based on 
the existence or non-existence of facts.  CLIPS provides the mechanism 
(the inference engine) which attempts to match the rules to the current 
state of the system (as represented by the fact-list) and applies the 
actions.  

(defrule <rule-name> [<comment>]
    [<declaration>]              
    <conditional-element>*       
    =>
    <action>*)  

DECLARATIONS
------------------------------------------------------------------
<declaration>           ::= (declare <rule-property>+)

<rule-property>         ::= (salience <integer-expression>) |
                            (auto-focus <boolean-symbol>)

CONDITIONAL ELEMENTS
------------------------------------------------------------------
<conditional-element>   ::= <pattern-CE> | <assigned-pattern-CE> | 
                            <not-CE> | <and-CE> | <or-CE> |
                            <logical-CE> | <test-CE> |
                            <exists-CE> | <forall-CE>

<test-CE>               ::= (test <function-call>)

<not-CE>                ::= (not <conditional-element>) 

<and-CE>                ::= (and <conditional-element>+)
 
<or-CE>                 ::= (or <conditional-element>+)  
 
<exists-CE>             ::= (exists <conditional-element>+)

<forall-CE>             ::= (forall <conditional-element>
                                    <conditional-element>+)

<logical-CE>            ::= (logical <conditional-element>+)

PATTERN CONDITIONAL ELEMENT
------------------------------------------------------------------
<assigned-pattern-CE>   ::= ?<variable-symbol> <- <pattern-CE>

<pattern-CE>            ::= <ordered-pattern-CE> | 
                            <template-pattern-CE> |
                            <object-pattern-CE>

<ordered-pattern-CE>    ::= (<symbol> <constraint>*)

<template-pattern-CE>   ::= (<deftemplate-name <LHS-slot>*)

<object-pattern-CE>     ::= (object <attribute-constraint>*)

<attribute-constraint>  ::= (is-a <constraint>) |
                            (name <constraint>) |
                            (<slot-name> <constraint>*)

<LHS-slot>              ::= <single-field-LHS-slot> | 
                            <multifield-LHS-slot>

<LHS-slot>              ::= <single-field-LHS-slot> | 
                            <multifield-LHS-slot>

<single-field-LHS-slot> ::= (<slot-name> <constraint>)

<multifield-LHS-slot>   ::= (<slot-name> <constraint>*)

PATTERN CONSTRAINTS
------------------------------------------------------------------
<constraint>            ::= ? | $? | <connected-constraint>

<connected-constraint>  
                ::= <single-constraint> |
                    <single-constraint> & <connected-constraint> |
                    <single-constraint> | <connected-constraint>

<single-constraint>     ::= <term> | ~<term>
                     
<term>                  ::= <constant> | 
                            <single-field-variable> |
                            <multifield-variable> |
                            :<function-call> |
                            =<function-call>
                            
END-ENTRY 

DEFFACTS

 CONSTRUCT_SUMMARY
  DEFFACTS
  
With the deffacts construct, a list of facts can be defined which are 
automatically asserted whenever the reset command is performed.  
Facts asserted through deffacts may be retracted or pattern matched like 
any other fact.  The initial fact-list, including any defined deffacts, 
is always reconstructed after a reset command.

The syntax of the deffacts construct is:

(deffacts <deffacts-name> [<comment>]
   <RHS-pattern>*)

END-ENTRY 

DEFTEMPLATE

 CONSTRUCT_SUMMARY
  DEFTEMPLATE
  
Ordered facts encode information positionally.  To access that information, 
a user must know not only what data is stored in a fact but which field 
contains the data.  Non-ordered (or deftemplate) facts provide the user 
with the ability to abstract the structure of a fact by assigning names 
to each field found within the fact.  The deftemplate construct is 
used to create a template which can then be used by non-ordered facts to 
access fields of the fact by name.  The deftemplate construct is analogous 
to a record or structure definition in programming languages such as Pascal 
and C.

The syntax of the deftemplate construct is:

(deftemplate <deftemplate-name> [<comment>]
   <slot-definition>*)

<slot-definition>         ::= <single-slot-definition> | 
                              <multislot-definition>

<single-slot-definition>  ::= (slot <slot-name> 
                                    <template-attribute>*)

<multislot-definition>    ::= (multislot <slot-name> 
                                         <template-attribute>*)

<template-attribute>      ::= <default-attribute> |
                              <constraint-attribute>

<default-attribute>  
                   ::= (default ?DERIVE | ?NONE | <expression>*) |
                       (default-dynamic <expression>*)

END-ENTRY 

DEFGLOBAL

 CONSTRUCT_SUMMARY
  DEFGLOBAL
  
With the defglobal construct, global variables can be defined, set, and 
accessed within the CLIPS environment.  Global variables can be accessed 
as part of the pattern matching process, but changing them does not invoke 
the pattern matching process.  The bind function is used to set the value 
of global variables.

The syntax of the defglobal construct is:

<defglobal-construct> ::= (defglobal [<defmodule-name>] 
                             <global-assignment>*)

<global-assignment>   ::= <global-variable> = <expression>

<global-variable>     ::= ?*<symbol>*


END-ENTRY 

DEFFUNCTION

 CONSTRUCT_SUMMARY
  DEFFUNCTION
  
With the deffunction construct, new functions may be defined directly in 
CLIPS.  Deffunctions are equivalent in use to other functions in CLIPS.  
The only differences between user-defined external functions and 
deffunctions are that deffunctions are written in CLIPS and executed 
by CLIPS interpretively and user-defined external functions are written 
in an external language, such as C, and executed by CLIPS directly.  
Also, deffunctions allow the addition of new functions without having to 
recompile and relink CLIPS.

The syntax of the deffunction construct is:

(deffunction <name> [<comment>]
    (<regular-parameter>* [<wildcard-parameter>])
    <action>*)

<regular-parameter>  ::= <single-field-variable>
<wildcard-parameter> ::= <multifield-variable>

END-ENTRY 

DEFGENERIC/DEFMETHOD

 CONSTRUCT_SUMMARY
  DEFGENERIC/DEFMETHOD
  
With the defgeneric/defmethod constructs, new generic functions may be written 
directly in CLIPS.  Generic functions are similar to deffunctions because 
they can be used to define new procedural code directly in CLIPS, and they can 
be called like any other function. However, generic functions are much more 
powerful because they can do different things depending on the types 
(or classes) and number of their arguments. For example, a '+' operator could 
be defined which performs concatenation for strings but still performs 
arithmetic addition for numbers.  Generic functions are comprised of 
multiple components called methods, where each method handles different 
cases of arguments for the generic function.  A generic function which has 
more than one method is said to be overloaded.

A generic function is comprised of a header (similar to a forward declaration) 
and zero or more methods.  A generic function header can either be explicitly 
declared by the user or implicitly declared by the definition of at least one 
method. The defgeneric construct is used to specify the generic function 
header,
and the defmethod construct is used for each of the generic function's 
methods.

The syntax of the defgeneric/defmethod constructs is:

(defgeneric <name> [<comment>])

(defmethod <name> [<index>] [<comment>]
    (<parameter-restriction>* [<wildcard-parameter>])
    <action>*)

<parameter-restriction> ::= <single-field-variable> |
                            (<single-field-variable> <type>* [<query>])

<wildcard-parameter>    ::= <multifield-variable>

<type>                  ::= <class-name>

<query>                 ::= <global-variable> | <function-call>
                            
END-ENTRY 

DEFCLASS

 CONSTRUCT_SUMMARY
  DEFCLASS

A defclass is a construct for specifying the properties (slots) of a class of 
objects.  A defclass consists of four elements: 1) a name, 2) a list of 
superclasses from which the new class inherits slots and message-handlers, 
3)  a specifier saying whether or not the creation of direct instances of the 
new class is allowed and 4) a list of slots specific to the new class.  All 
user-defined classes must inherit from at least one class, and to this end 
COOL provides predefined system classes for use as a base in the derivation 
of new classes.

Any slots explicitly given in the defclass override those gotten from 
inheritance.  COOL applies rules to the list of superclasses to generate a 
class precedence list for the new class.  Facets further describe slots.  
Some examples of facets include: default value, cardinality, and types of 
access allowed.

The syntax of the defclass construct is:

(defclass <name> [<comment>]
  (is-a <superclass-name>+)
  [<role>]
  [<pattern-match-role>]
  <slot>*
  <handler-documentation>*)

<role>  ::= (role concrete | abstract)

<pattern-match-role> 
        ::= (pattern-match reactive | non-reactive)

<slot>  ::= (slot <name> <facet>*) |
            (single-slot <name> <facet>*) |
            (multislot <name> <facet>*)

<facet> ::=  <default-facet> | <storage-facet> |
             <access-facet> | <propagation-facet> | 
             <source-facet> | <pattern-match-facet> |
             <visibility-facet> | <create-accessor-facet>
             <override-message-facet> | <constraint-attributes>
 
<default-facet> ::= 
           (default ?DERIVE | ?NONE | <expression>*) |
           (default-dynamic <expression>*)

<storage-facet> ::= (storage local | shared)

<access-facet> 
       ::= (access read-write | read-only | initialize-only)

<propagation-facet> ::= (propagation inherit | no-inherit)

<source-facet> ::= (source exclusive | composite)

<pattern-match-facet> 
       ::= (pattern-match reactive | non-reactive)

<visibility-facet> ::= (visibility private | public)

<create-accessor-facet> 
     ::= (create-accessor ?NONE | read | write | read-write)

<override-message-facet> 
     ::= (override-message ?DEFAULT | <message-name>)
                                           
<handler-documentation> 
       ::= (message-handler <name> [<handler-type>])

<handler-type> ::= primary | around | before | after

END-ENTRY 

DEFINSTANCES

 CONSTRUCT_SUMMARY
  DEFINSTANCES
  
Similar to deffacts, the definstances construct allows the specification of 
instances which will be created every time the reset command is executed.  
On every reset all current instances receive a delete message, and the 
equivalent of a make-instance function call is made for every instance 
specified in definstances constructs.

The syntax of the definstances construct is:

<definstances-construct> 
                ::= (definstances <definstances-name> [<comment>]
                       <instance-template>*)

<instance-template>   ::= (<instance-definition>)

<instance-definition> ::= <instance-name-expression> of
                             <class-name-expression>
                             <slot-override>*

<slot-override>       ::= (<slot-name-expression> <expression>*)

END-ENTRY 

DEFMESSAGE-HANDLER

 CONSTRUCT_SUMMARY
  DEFMESSAGE-HANDLER
  
Objects are manipulated by sending them messages via the function send.  The 
result of a message is a useful return-value or side-effect.  A 
defmessage-handler is a construct for specifying the behavior of a class of 
objects in response to a particular message.  The implementation of a message 
is made up of pieces of procedural code called message-handlers (or handlers 
for short).  Each class in the class precedence list of an object's class can 
have handlers for a message.  In this way, the object's class and all its 
superclasses share the labor of handling the message.  Each class's handlers 
handle the part of the message which is appropriate to that class.  Within a 
class, the handlers for a particular message can be further subdivided into 
four types or categories: primary, before, after and around.

A defmessage-handler is comprised of seven elements: 1) a class name to which 
to attach the handler (the class must have been previously defined), 2) a 
message name to which the handler will respond, 3) an optional type (the 
default is primary), 4) an optional comment, 5) a list of parameters that will
be passed to the handler during execution, 6) an optional wildcard parameter 
and 7) a series of expressions which are executed in order when the handler 
is called.  The return-value of a message-handler is the evaluation of the 
last 
expression in the body.

The syntax of the defmessage-handler construct is:
  
(defmessage-handler <class-name> <message-name>
   [<handler-type>] [<comment>]
   (<parameter>* [<wildcard-parameter>])
   <action>*)

<handler-type>       ::= around | before | primary | after

<parameter>          ::= <single-field-variable>

<wildcard-parameter> ::= <multifield-variable>

END-ENTRY 

DEFMODULE

 CONSTRUCT_SUMMARY
  DEFMODULE
  
CLIPS provides support for the modular development and execution of knowledge 
bases with the defmodule construct. CLIPS modules allow a set of constructs to 
be grouped together such that explicit control can be maintained over 
restricting the access of the constructs by other modules. This type of 
control is similar to global and local scoping used in languages such as C or 
Ada. By restricting access to deftemplate and defclass constructs, modules can 
function as blackboards, permitting only certain facts and instances to be 
seen by other modules. Modules are also used by rules to provide execution 
control.

The syntax of the defmodule construct is:

<defmodule-construct> ::= (defmodule <module-name> [<comment>] 
                             <port-spec>*)

<port-specification>  ::= (export <port-item>) |
                          (import <module-name> <port-item>)
                
<port-item>           ::= ?ALL |
                          ?NONE |
                          <port-construct> ?ALL |
                          <port-construct> ?NONE |
                          <port-construct> <construct-name>+ 

<port-construct>      ::= deftemplate | defclass |
                          defglobal | deffunction | defgeneric

END-ENTRY 

CONSTRAINT_ATTRIBUTES

 CONSTRUCT_SUMMARY
  CONSTRAINT_ATTRIBUTES
  
Constraint attributes can be associated with deftemplate and defclass slots so 
that type checking can be performed on slot values when template facts and 
instances are created. The constraint information is also analyzed for the 
patterns on the LHS of a rule to determine if the specified constraints 
prevent the rule from ever firing.

The syntax for constraint attributes is:
  
<constraint-attribute> ::= <type-attribute> |
                           <allowed-constant-attribute> |
                           <range-attribute> |
                           <cardinality-attribute>
                           <default-attribute>

<type-attribute>       ::= (type <type-specification>)

<type-specification>   ::= <allowed-type>+ | ?VARIABLE

<allowed-type>         ::= SYMBOL | STRING | LEXEME |
                           INTEGER | FLOAT | NUMBER | 
                           INSTANCE-NAME | INSTANCE-ADDRESS |
                           INSTANCE |
                           EXTERNAL-ADDRESS | FACT-ADDRESS

<allowed-constant-attribute> 
                       ::= (allowed-symbols <symbol-list>) |
                           (allowed-strings <string-list>) |
                           (allowed-lexemes <lexeme-list> |
                           (allowed-integers <integer-list>) |
                           (allowed-floats <float-list>) |
                           (allowed-numbers <number-list>) |
                           (allowed-instance-names <instance-list>) |
                           (allowed-values <value-list>) |

<symbol-list>          ::= <symbol>+ | ?VARIABLE

<string-list>          ::= <string>+ | ?VARIABLE

<lexeme-list>          ::= <lexeme>+ | ?VARIABLE

<integer-list>         ::= <integer>+ | ?VARIABLE

<float-list>           ::= <float>+ | ?VARIABLE

<number-list>          ::= <number>+ | ?VARIABLE

<instance-name-list>   ::= <instance-name>+ | ?VARIABLE

<value-list>           ::= <constant>+ | ?VARIABLE

<range-attribute>      ::= (range <range-specification> 
                                  <range-specification>)

<range-specification>  ::= <number> | ?VARIABLE

<cardinality-attribute>    
                    ::= (cardinality <cardinality-specification> 
                                     <cardinality-specification>)

<cardinality-specification> ::= <integer> | ?VARIABLE

END-ENTRY 

FUNCTION_SUMMARY

 FUNCTION_SUMMARY

This section gives a general overview of the available CLIPS functions.

Subtopics: 
PREDICATE_FUNCTIONS        DEFRULE_FUNCTIONS
MULTIFIELD_FUNCTIONS       AGENDA_FUNCTIONS
STRING_FUNCTIONS           DEFGLOBAL_FUNCTIONS
IO_FUNCTIONS               DEFFUNCTION_FUNCTIONS
MATH_FUNCTIONS             GENERIC_FUNCTION_FUNCTIONS
PROCEDURAL_FUNCTIONS       COOL_FUNCTIONS
MISCELLANEOUS_FUNCTIONS    DEFMODULE_FUNCTIONS
DEFTEMPLATE_FUNCTIONS      SEQUENCE_EXPANSION_FUNCTIONS
FACT_FUNCTIONS

END-ENTRY 

PREDICATE_FUNCTIONS

 FUNCTION_SUMMARY
  PREDICATE_FUNCTIONS
  
The following functions perform predicate tests and return
either TRUE or FALSE.

NUMBERP: Returns TRUE for integers and floats.
(numberp <expression>)

FLOATP: Returns TRUE for floats.
(floatp <expression>)

INTEGERP: Returns TRUE for integers.
(integerp <expression>)

LEXEMEP: Returns TRUE for symbols and strings.
(numberp <expression>)

STRINGP: Returns TRUE for strings.
(stringp <expression>)

SYMBOLP: Returns TRUE for symbols.
(symbolp <expression>)

EVENP: Returns TRUE for even numbers.
(evenp <expression>)

ODDP: Returns TRUE for odd numbers.
(oddp <expression>)

MULTIFIELDP: Returns TRUE for multifield values.
(multifieldp <expression>)

POINTERP: Returns TRUE for external addresses.
(pointerp <expression>)

EQ: Returns TRUE if the 1st argument is equal in type and value
    to all subsequent arguments.
(eq <expression> <expression>+)

NEQ: Returns TRUE if the 1st argument is not equal in type and
     value to all subsequent arguments.
(neq <expression> <expression>+)

=: Returns TRUE if the 1st argument is equal in value
   to all subsequent arguments.
(= <numeric-expression> <numeric-expression>+)

<>: Returns TRUE if the 1st argument is not equal in value
    to all subsequent arguments.
(<> <numeric-expression> <numeric-expression>+)

>: Returns TRUE if each argument is greater in value than the
   argument following it.
(> <numeric-expression> <numeric-expression>+)

>=: Returns TRUE if each argument is greater than or equal to 
    in value than the argument following it.
(>= <numeric-expression> <numeric-expression>+)

<: Returns TRUE if each argument is less in value than the
   argument following it.
(< <numeric-expression> <numeric-expression>+)

<=: Returns TRUE if each argument is less than or equal to 
    in value than the argument following it.
(<= <numeric-expression> <numeric-expression>+)
   
AND: Returns TRUE if all arguments evaluate to a non-FALSE value.
(and <expression>+)

OR: Returns TRUE if any argument evaluates to a non-FALSE value.
(or <expression>+)

NOT: Returns TRUE if its only argument evaluates to FALSE.
(not <expression>)
   
END-ENTRY 

MULTIFIELD_FUNCTIONS

 FUNCTION_SUMMARY
  MULTIFIELD_FUNCTIONS

The following functions operate on multifield values.

CREATE$: Appends its arguments together to create a multifield value.
(create$ <expression>*)

NTH$: Returns the specified field of a multifield value.
(nth$ <integer-expression> <multifield-expression>)

MEMBER$: Returns the position of a single-field value within a multifield 
value.
(member$ <single-field-expression> <multifield-expression>)

SUBSETP: Returns TRUE if the first argument is a subset of the second 
argument.
(subsetp <multifield-expression> <multifield-expression>)

DELETE$: Deletes the specified range from a multifield value.
(delete$ <multifield-expression>
         <begin-integer-expression> <end-integer-expression>)

EXPLODE$: Creates a multifield value from a string.
(explode$ <string-expression>)

IMPLODE$: Creates a string from a multifield value.
(implode$ <multifield-expression>)

SUBSEQ$: Extracts the specified range from a multifield value.
(subseq$ <multifield-expression> 
         <begin-integer-expression> <end-integer-expression>)

REPLACE$: Replaces the specified range of a multifield value with a 
          set of values.
(replace$ <multifield-expression>
          <begin-integer-expression> <end-integer-expression> 
          <single-or-multifield-expression>+)

INSERT$: Inserts one or more values in a multifield.
(insert$ <multifield-expression> <integer-expression> 
         <single-or-multifield-expression>+)

FIRST$: Returns the first field of a multifield.
(first$ <multifield-expression>)

REST$: Returns all but the first field of a multifield.
(rest$ <multifield-expression>)

LENGTH$: Returns the number of fields in a multifield value.
(length$ <multifield-expression>)

DELETE-MEMBER$: Deletes specific values contained within a multifield 
                value and returns the modified multifield value.
(delete-member$ <multifield-expression> <expression>+)

REPLACE-MEMBER$: Replaces specific values contained within a multifield 
                 value and returns the modified multifield value.
(replace-member$ <multifield-expression> <substitute-expression>
                 <search-expression>+)

END-ENTRY 

STRING_FUNCTIONS

 FUNCTION_SUMMARY
  STRING_FUNCTIONS

The following functions perform operations that are related to strings.

STR-CAT: Concatenates its arguments to form a single string.
(str-cat <expression>*)

SYM-CAT: Concatenates its arguments to form a single symbol.
(sym-cat <expression>*)

SUB-STRING: Retrieves a subportion from a string.
(sub-string <integer-expression> <integer-expression> <string-expression>)

STR-INDEX: Returns the position of the first argument within the second 
           argument.
(str-index <lexeme-expression> <lexeme-expression>)

EVAL: Evaluates a string as though it were entered at the command prompt.
      Only allows functions to be evaluated.
(eval <lexeme-expression>)

BUILD: Evaluates a string as though it were entered at the command prompt.
       Only allows constructs to be evaluated.
(build <lexeme-expression>)

UPCASE: Converts lowercase characters in a string or symbol to uppercase.
(upcase <lexeme-expression>)

LOWCASE: Converts uppercase characters in a string or symbol to lowercase.
(lowcase <lexeme-expression>)

STR-COMPARE: Lexigraphically compares two strings.
(str-compare <lexeme-expression> <lexeme-expression>)

STR-LENGTH: Returns the length of a string.
(str-length <lexeme-expression>)

CHECK-SYNTAX: Allows the text representation of a construct or function
              call to be checked for syntax and semantic errors.
(check-syntax <construct-or-function-string>)

STRING-TO-FIELD: Parses a string and converts its contents to a primitive 
                 data type.
(string-to-field  <string-or-symbol-expression>)

END-ENTRY 

IO_FUNCTIONS

 FUNCTION_SUMMARY
  IO_FUNCTIONS
  
The following functions perform I/O operations.

OPEN: Opens a file.
(open <file-name> <logical-name> [<mode>])
<mode> ::= "r" | "w" | "r+" | "a" | "wb"

CLOSE: Closes a file.
(close [<logical-name>])

PRINTOUT: Sends unformated output to the specified logical name.
(printout <logical-name> <expresion>*)

READ: Reads a single-field value from the specified logical name.
(read [<logical-name>])

READLINE: Reads an entire line as a string from the specified 
          logical name.
(readline [<logical-name>])

FORMAT: Sends formated output to the specified logical name.
(format <logical-name> <string-expression> <expression>*)

RENAME: Changes the name of a file.
(rename <old-file-name> <new-file-name>)

REMOVE: Deletes a file.
(remove <file-name>)

GET-CHAR: Allows a single character to be retrieved from a 
          logical name.
(get-char [<logical-name>])

READ-NUMBER: Allows a user to input a single number using the 
             localized format.
(read-number [<logical-name>])

SET-LOCALE: Allows a locale to be specified for the numeric format
            behavior of the format and read-number functions.
(set-locale [<locale-string>])

END-ENTRY 
2MBEGIN-ENTRY-MATH_FUNCTIONS
 FUNCTION_SUMMARY
  MATH_FUNCTIONS

The math functions have been divided into three broad categories. The
basic math functions are always provided with CLIPS. The trigonometric
and extended math functions are included as part of the extended math
package.

Subtopics: 
BASIC_MATH_FUNCTIONS       EXTENDED_MATH_FUNCTIONS
TRIGONOMETRIC_FUNCTIONS    

END-ENTRY 

BASIC_MATH_FUNCTIONS

 FUNCTION_SUMMARY
  MATH_FUNCTIONS
    BASIC_MATH_FUNCTIONS
    
The following functions perform basic mathematical operations.

+: Returns the sum of its arguments.
(+ <numeric-expression> <numeric-expression>+)

-: Returns the first argument minus all subsequent arguments.
(- <numeric-expression> <numeric-expression>+)

*: Returns the product of its arguments.
(* <numeric-expression> <numeric-expression>+)

/: Returns the first argument divided by all subsequent arguments. 
(/ <numeric-expression> <numeric-expression>+)

DIV: Returns the first argument divided by all subsequent arguments
     using integer division. 
(div <numeric-expression> <numeric-expression>+)

MAX: Returns the value of its largest numeric argument.
(max <numeric-expression>+)

MIN: Returns the value of its smallest numeric argument.
(min <numeric-expression>+)

ABS: Returns the absolute value of its only argument.
(abs <numeric-expression>)

FLOAT: Converts its only argument to a float.
(float <numeric-expression>)

INTEGER: Converts its only argument to an integer.
(integer <numeric-expression>)

END-ENTRY 

TRIGONOMETRIC_FUNCTIONS

 FUNCTION_SUMMARY
  MATH_FUNCTIONS
    TRIGONOMETRIC_FUNCTIONS
    
The following trigonometric functions take one numeric argument  
and return a float.  The argument is expected to be in radians.
These functions are part of the extended math package.
    
FUNCTION         RETURNS
----------------------------------------
acos             arccosine
acosh            hyperbolic arccosine
acot             arccotangent
acoth            hyperbolic arccotangent
acsc             arccosecant
acsch            hyperbolic arccosecant
asec             arcsecant
asech            hyperbolic arcsecant
asin             arcsine
asinh            hyperbolic arcsine
atan             arctangent
atanh            hyperbolic arctangent
cos              cosine
cosh             hyperbolic cosine
cot              cotangent
coth             hyperbolic tangent
csc              cosecant
csch             hyperbolic cosecant
sec              secant
sech             hyperbolic secant
sin              sine
sinh             hyperbolic sine
tan              tangent
tanh             hyperbolic tangent

END-ENTRY 

EXTENDED_MATH_FUNCTIONS

 FUNCTION_SUMMARY
  MATH_FUNCTIONS
    EXTENDED_MATH_FUNCTIONS
    
The following functions perform extended mathematical operations
and are included as part of the extended math package.
    
DEG-GRAD: Converts its only argument from degrees to gradients.
(deg-grad <numeric-expression>)

DEG-RAD: Converts its only argument from degrees to radians.
(deg-rad <numeric-expression>)

GRAD-DEG: Converts its only argument from gradients to degrees.
(grad-deg <numeric-expression>)

RAD-DEG: Converts its only argument from radians to degrees.
(rad-deg <numeric-expression>)

PI: Returns the value of pi.
(pi)

SQRT: Returns the square root of its only argument.
(sqrt <numeric-expression>)

**: Raises its first argument to the power of its second argument.
(** <numeric-expression> <numeric-expression>)

EXP: Raises the value e to the power of its only argument.
(exp <numeric-expression>)

LOG: Returns the logarithm base e of its only argument.
(log <numeric-expression>)

LOG10: Returns the logarithm base 10 of its only argument.
(log10 <numeric-expression>)

ROUND: Rounds its argument toward the closest integer or negative
       infinity if exactly between two integers.
(round <numeric-expression>)

MOD: Returns the remainder of the result of dividing its first argument 
     by its second argument (assuming that the result of division must 
     be an integer).  
(mod <numeric-expression> <numeric-expression>)

END-ENTRY 

PROCEDURAL_FUNCTIONS

 FUNCTION_SUMMARY
  PROCEDURAL_FUNCTIONS

The following are functions which provide procedural programming
capabilities as found in languages such as Pascal, C, and Ada.

BIND: Binds a variable to a new value.
(bind <variable> <expression>*)

IF: Allows conditional execution of a group of actions.
(if <expression> then <action>* [else <action>*])

WHILE: Allows conditional looping.
(while <expression> [do] <action>*)

LOOP-FOR-COUNT: Allows simple iterative looping.
(loop-for-count <range-spec> [do] <action>*)
<range-spec>  ::= <end-index> |
                  (<loop-variable> [<start-index> <end-index>])
<start-index> ::= <integer-expression>
<end-index>   ::= <integer-expression>

PROGN: Evaluates all arguments and returns the value of the last 
       argument evaluated.
(progn <expression>*)

PROGN$: Performs a set of actions for each field of a multifield value.
(progn$ <list-spec> <expression>*)
<list-spec> ::= <multifield-expression> |
                (<list-variable> <multifield-expression>)

RETURN: Immediately terminates the currently executing deffunction,
        generic function method, message-handler, defrule RHS, or
        certain instance set query functions and if a value is 
        specified, returns this value as the result of the executing 
        construct.
(return [<expression>])

BREAK: Immediately terminates the currently iterating while loop,
       progn execution, or certain instance set query functions.
(break)

SWITCH: Allows a particular group of actions to be performed based
        on a specified value.
(switch <test-expression>
   <case-statement>*
   [<default-statement>])
<case-statement> ::= (case <comparison-expression> then <action>*)
<default-statement> ::= (default <action>*)

END-ENTRY 

MISCELLANEOUS_FUNCTIONS

 FUNCTION_SUMMARY
  MISCELLANEOUS_FUNCTIONS
    
The following are additional functions for use within CLIPS.

GENSYM: Returns a special sequenced symbol.
(gensym)

GENSYM*: Returns a special unique sequenced symbol.
(gensym*)

SETGEN: Sets the starting number used by gensym and gensym*.
(setgen <integer-expression>)

RANDOM: Returns a "random" integer value.
(random [<start-integer-expression> <end-integer-expression>])

SEED: Seeds the random number generator used by random.
(seed <integer-expression>)

TIME: Returns a float representing the elapsed seconds since 
      the system reference time.
(time)

LENGTH: Returns an integer for the number of fields in a multifield value
        or the length in characters of a string or symbol.
(length <lexeme-or-multifield-expression>)

GET-FUNCTION_RESTRICTIONS: Returns the restriction string associated with 
                           a CLIPS or user defined function.
(get-function-restrictions <function-name>)

SORT: Allows a list of values to be sorted based on a user specified
      comparison function.
(sort <comparison-function-name> <expression>*)

FUNCALL: Constructs a function call from its arguments and then
         evaluates the function call.
(funcall (function-name> <expression>*)

TIMER: Returns the number of seconds elapsed evaluating a series of 
       expressions.
(timer <expression>*)

END-ENTRY 

DEFTEMPLATE_FUNCTIONS


The following functions provide ancillary capabilities for the deftemplate 
construct.

DEFTEMPLATE-MODULE: Returns the module in which the specified deftemplate is
                    defined.
(deftemplate-module <deftemplate-name>)

DEFTEMPLATE-SLOT-ALLOWED-VALUES: Returns a multifield containing the allowed 
                                 values for a deftemplate slot.
(deftemplate-slot-allowed-values <deftemplate-name> <slot-name>)

DEFTEMPLATE-SLOT-CARDINALITY: Returns a multifield containing the minimum and 
                              maximum cardinality allowed for a multifield slot.
(deftemplate-slot-cardinality <deftemplate-name> <slot-name>)


DEFTEMPLATE-SLOT-DEFAULTP: Returns either static, dynamic, or FALSE to indicate
                           whether the deftemplate slot has a default.
(deftemplate-slot-defaultp <deftemplate-name> <slot-name>)

DEFTEMPLATE-SLOT-DEFAULT-VALUE: Returns the default value for the deftemplate
                                slot.
(deftemplate-slot-default-value <deftemplate-name> <slot-name>)

DEFTEMPLATE-SLOT-EXISTP: Returns TRUE if the specified deftemplate slot exists,
                         otherwise FALSE.
(deftemplate-slot-existp <deftemplate-name> <slot-name>)

DEFTEMPLATE-SLOT-MULTIP: Returns TRUE if the specified deftemplate slot is a
                         multifield slot, otherwise FALSE.
(deftemplate-slot-multip <deftemplate-name> <slot-name>)

DEFTEMPLATE-SLOT-NAMES: Returns the slot names associated with the deftemplate
                        in a multifield value.
(deftemplate-slot-names <deftemplate-name>)

DEFTEMPLATE-SLOT-RANGE: Returns a multifield containing the minimum and 
                        maximum numeric range allowed for a slot.
(deftemplate-slot-range <deftemplate-name> <slot-name>)

DEFTEMPLATE-SLOT-SINGLEP: Returns TRUE if the specified deftemplate slot is a
                         single-field slot, otherwise FALSE.
(deftemplate-slot-singlep <deftemplate-name> <slot-name>)

DEFTEMPLATE-SLOT-TYPES: Returns a multifield containing the primitive types 
                        allowed for a slot.
(deftemplate-slot-types <deftemplate-name> <slot-name>)

GET-DEFTEMPLATE-LIST: Returns the list of all deftemplates in the specified
                      module (or the current module if unspecified).
(get-deftemplate-list [<module-name>])

END-ENTRY 

FACT_FUNCTIONS

The following actions are used for assert, retracting, and modifying facts.

ASSERT: Adds a fact to the fact-list.
(assert <RHS-pattern>+)

RETRACT: Removes a fact from the fact-list.
(retract <retract-specifier>+ | *)
<retract-specifier> ::= <fact-specifier> | <integer-expression>

MODIFY: Modifies a deftemplate fact in the fact-list.
(modify <fact-specifier> <RHS-slot>*)

DUPLICATE: Duplicates a deftemplate fact in the fact-list.
(duplicate <fact-specifier> <RHS-slot>*)

ASSERT-STRING: Converts a string into a fact and asserts it.
(assert-string <string-expression>)

FACT-INDEX: Returns the fact index of a fact address.
(fact-index <fact-address>)

FACT-EXISTP: Returns TRUE if the fact specified by its fact-index or 
             fact-address arguments exists, otherwise FALSE.
(fact-existp <fact-address-or-index>)

FACT-RELATION: Returns the deftemplate (relation) name associated with 
               the fact.
(fact-relation <fact-address-or-index>)

FACT-SLOT-NAMES: Returns the slot names associated with the fact.
(fact-slot-names <fact-address-or-index>)

FACT-SLOT-VALUE: Returns the value of the specified slot from the 
                 specified fact.
(fact-slot-value <fact-address-or-index> <slot-name>)

GET-FACT-LIST: Returns a multifield containing the list of visible facts.
(get-fact-list [<module-name>])

END-ENTRY 

DEFFACTS_FUNCTIONS

The following functions provide ancillary capabilities for the deffacts 
construct.

GET-DEFFACTS-LIST: Returns the list of all deffacts in the specified
                   module (or the current module if unspecified).
(get-deffacts-list [<module-name>])

DEFFACTS-MODULE: Returns the module in which the specified deffacts is
                 defined.
(deffacts-module <deffacts-name>)

END-ENTRY 

DEFRULE_FUNCTIONS

The following functions provide ancillary capabilities for the defrule 
construct.

GET-DEFRULE-LIST: Returns the list of all defrules in the specified
                  module (or the current module if unspecified).
(get-defrule-list [<module-name>])

DEFRULE-MODULE: Returns the module in which the specified defrule is
                defined.
(defrule-module <defrule-name>)

END-ENTRY 

AGENDA_FUNCTIONS

The following functions provide ancillary capabilities for manipulating the 
agenda.

GET-FOCUS: Returns the module name of the current focus.
(get-focus)

GET-FOCUS-STACK: Returns all of the module names in the focus stack as a
                 multifield value.
(get-focus-stack)

POP-FOCUS: Removes the current focus from the focus stack and returns the
           module name of the current focus.
(pop-focus)

END-ENTRY 

DEFGLOBAL_FUNCTIONS

The following functions provide ancillary capabilities for the defglobal 
construct.

GET-DEFGLOBAL-LIST: Returns the list of all defglobals in the specified
                    module (or the current module if unspecified).
(get-defglobal-list [<module-name>])

DEFGLOBAL-MODULE: Returns the module in which the specified defglobal is
                  defined.
(defglobal-module <defglobal-name>)

END-ENTRY 

DEFFUNCTION_FUNCTIONS

The following functions provide ancillary capabilities for the deffunction 
construct.

GET-DEFFUNCTION-LIST: Returns the list of all deffunctions in the specified
                      module (or the current module if unspecified).
(get-deffunction-list [<module-name>])

DEFFUNCTION-MODULE: Returns the module in which the specified deffunction 
                    is defined.
(deffunction-module <deffunction-name>)

END-ENTRY 

GENERIC_FUNCTION_FUNCTIONS

 FUNCTION_SUMMARY
  GENERIC_FUNCTION_FUNCTIONS
    
The following functions provide ancillary capabilities for generic 
function methods.

GET-DEFGENERIC-LIST: Returns the list of all defgenerics in the specified
                     module (or the current module if unspecified).
(get-defgeneric-list [<module-name>])

DEFGENERIC-MODULE: Returns the module in which the specified defgeneric 
                   is defined.
(defgeneric-module <defgeneric-name>)

GET-DEFMETHOD-LIST: Returns the list of all defmethods in the current
                    module (or just the methods associated with the
                    specified defgeneric).
(get-defmethod-list [<defgeneric-name>])

TYPE: Returns a symbol which is the name of the type (or class) 
       of its of argument.
(type <expression>)

NEXT-METHODP: If called from a method for a generic function, the function 
              next-methodp will return the symbol TRUE if there is another 
              method shadowed by the current one. Otherwise, the function
              will return the symbol FALSE.
(next-methodp)

CALL-NEXT-METHOD: Calls the next shadowed method.
(call-next-method)

OVERRIDE-NEXT-METHOD: Calls the next shadowed method allowing new 
                      arguments to be provided.
(override-next-method <expression>*)

CALL-SPECIFIC-METHOD: Calls a particular method of a generic function without
                      regards to method precedence.
(call-specific-method <generic-function> <method-index> <expression>*)

GET-METHOD-RESTRICTIONS: Returns a multifield value containing information
                         about the restrictions for the specified method.
(get-method-restrictions <generic-function-name> <method-index>)

END-ENTRY 

COOL_FUNCTIONS

 FUNCTION_SUMMARY
  COOL_FUNCTIONS

The functions manipulating the CLIPS Object-Oriented Language (COOL)
are divided into five categories. 

Subtopics: 
CLASS_FUNCTIONS                    INSTANCE_SLOT_FUNCTIONS
INSTANCE_MANIPULATION_FUNCTIONS    MESSAGE-HANDLER_FUNCTIONS  
DEFINSTANCES_FUNCTIONS             INSTANCE_PREDICATE_FUNCTIONS

END-ENTRY 

CLASS_FUNCTIONS

 FUNCTION_SUMMARY
  COOL_FUNCTIONS
    CLASS_FUNCTIONS

The following functions are used with classes. 

GET-DEFCLASS-LIST: Returns the list of all defclasses in the specified
                   module (or the current module if unspecified).
(get-defclass-list [<module-name>])

DEFCLASS-MODULE: Returns the module in which the specified defclass 
                   is defined.
(defclass-module <defclass-name>)

CLASS-EXISTP: Returns TRUE if the specified class is defined, FALSE otherwise.
(class-existp <class-name>)

SUPERCLASSP: Returns TRUE if the first class is a superclass of
             the second class, FALSE otherwise.
(superclassp <class1-name> <class2-name>)

SUBCLASSP: Returns TRUE if the first class is a subclass of
           the second class, FALSE otherwise.
(subclassp <class1-name> <class2-name>)

SLOT-EXISTP: Returns TRUE if the specified slot is present in the class, 
             FALSE otherwise. If the inherit keyword is specified, then
             the slot may be inherited.
(slot-existp <class-name> <slot-name> [inherit])

SLOT-WRITABLEP: Returns TRUE if the specified slot is writable, 
                otherwise FALSE.
(slot-writablep <class-name> <slot-name>)

SLOT-INITABLEP: Returns TRUE if the specified slot is initializable, 
                otherwise FALSE.
(slot-initablep <class-name> <slot-name>)

SLOT-PUBLICP: Returns TRUE if the specified slot is public, 
              otherwise FALSE.
(slot-initablep <class-name> <slot-name>)

SLOT-DIRECT-ACCESSP: Returns TRUE if the specified slot can be accessed 
                     directly, otherwise FALSE.
(slot-direct-accessp <class-name> <slot-name>)

MESSAGE-HANDLER-EXISTP: Returns TRUE if the specified message-handler is 
                        defined (directly, not by inheritance) for the 
                        class, FALSE otherwise.
(message-handler-existp <class-name> <handler-name> [<handler-type>])
<handler-type> ::= around | before | primary | after

CLASS-ABSTRACTP: Returns TRUE if the specified class is abstract,
                 FALSE otherwise.
(class-abstractp <class-name>)

CLASS-REACTIVEP: Returns TRUE if the specified class is reactive,
                 FALSE otherwise.
(class-reactivep <class-name>)

CLASS-SUPERCLASSES: Returns the names of the direct superclasses of a class in
                    a multifield variable. If the optional "inherit" argument 
                    is given, indirect superclasses are also included.
(class-superclasses <class-name> [inherit])

CLASS-SUBCLASSES: Returns the names of the direct subclasses of a class in a
                  multifield variable. If the optional "inherit" argument is
                  given, indirect subclasses are also included.
(class-subclasses <class-name> [inherit])

CLASS-SLOTS: Returns the names of the explicitly defined slots of a class in
             a multifield variable. If the optional inherit keyword is
             given, inherited slots are also included.
(class-slots <class-name> [inherit])

GET-DEFMESSAGE-HANDLER-LIST: Returns the class names, message names, and 
                             message types of the message-handlers directly 
                             attached to a class in a multifield variable. If 
                             the optional inherit keyword is given, inherited 
                             message-handlers are also included.
(get-defmessage-handler-list <class-name> [inherit])

SLOT-FACETS: Returns the facet values for the specified slot of a class in a
             multifield value.
(slot-facets <class-name> <slot-name>)

SLOT-SOURCES: Returns the names of the classes which provide facets for a 
              slot of a class in a multifield variable.
(slot-sources <class-name> <slot-name>)

SLOT-TYPES: Returns the names of the primitive types allowed for a slot
            in a multifield variable.
(slot-types <class-name> <slot-name>)

SLOT-CARDINALITY: Returns the minimum and maximum number of fields allowed 
                  for a multislot in a multifield variable.
(slot-cardinality <class-name> <slot-name>)

SLOT-ALLOWED-VALUES: Returns the allowed values for a slot in a  
                     multifield value.
(slot-allowed-values <class-name> <slot-name>)

SLOT-RANGE: Returns the minimum and maximum numeric values allowed
            for a slot.
(slot-range <class-name> <slot-name>)

SLOT-DEFAULT-VALUE: Returns the default value associated with a slot.
(slot-default-value <class-name> <slot-name>)

SET-CLASS-DEFAULTS-MODE: Sets the defaults mode used when classes are 
                         defined.
(set-class-defaults-mode <mode>)
<mode> ::= convenience | conservation

GET-CLASS-DEFAULTS-MODE: Returns the current defaults mode used when 
                         classes are defined.
(get-class-defaults-mode)

SLOT-ALLOWED-CLASSES: Returns the allowed classes for a slot in a
                      multifield value.
(slot-allowed-classes <class-name> <slot-name>)

END-ENTRY 

MESSAGE-HANDLER_FUNCTIONS

 FUNCTION_SUMMARY
  COOL_FUNCTIONS
    MESSAGE-HANDLER_FUNCTIONS

The following functions are used with message-handlers. 

NEXT-HANDLERP: Returns TRUE if there is another message-handler available
               for execution, FALSE otherwise.
(next-handlerp)

CALL-NEXT-HANDLER: Calls the next shadowed handler.
(call-next-handler)

OVERRIDE-NEXT-HANDLER: Calls the next shadowed handler and allows the 
                       arguments to be changed.
(override-next-handler <expression>*)

END-ENTRY 

DEFINSTANCES_FUNCTIONS

 FUNCTION_SUMMARY
  COOL_FUNCTIONS
    DEFINSTANCES_FUNCTIONS

The following functions are used with definstances. 

GET-DEFINSTANCES-LIST: Returns the list of all definstances in the specified
                       module (or the current module if unspecified).
(get-definstances-list [<module-name>])

DEFINSTANCES-MODULE: Returns the module in which the specified definstance 
                     is defined.
(definstances-module <definstances-name>)

END-ENTRY 

INSTANCE_MANIPULATION_FUNCTIONS

 FUNCTION_SUMMARY
  COOL_FUNCTIONS
    INSTANCE_MANIPULATION_FUNCTIONS

The following manipulation functions are used with instances. 

INIT-SLOTS: Implements the init message-handler attached to the class
            USER. This function should never be called directly unless
            an init message-handler is being defined such that the one
            attached to USER will never be called.
(init-slots)

UNMAKE-INSTANCE: Deletes the specified instance by sending it 
                 the delete message.
(unmake-instance <instance-expression> | *)

DELETE-INSTANCE: Deletes the active instance when called from within
                 the body of a message-handler.
(delete-instance)

CLASS: Returns a symbol which is the name of the class of its argument.
(class <object-expression>)

INSTANCE-NAME: Returns a symbol which is the name of its instance argument.
(instance-name <instance-expression>)

INSTANCE-ADDRESS: Returns the address of its instance argument.
(instance-address <instance-expression>)

SYMBOL-TO-INSTANCE-NAME: Converts a symbol to an instance name.
(symbol-to-instance-name <symbol-expression>)

INSTANCE-NAME-TO-SYMBOL: Converts an instance name to a symbol.
(instance-name-to-symbol <instance-name-expression>)

END-ENTRY 

INSTANCE_PREDICATE_FUNCTIONS

 FUNCTION_SUMMARY
  COOL_FUNCTIONS
    INSTANCE_PREDICATE_FUNCTIONS

The following predicate functions are used with instances. 

INSTANCEP: Returns TRUE if its argument is an instance name or instance
           address, FALSE otherwise.
(instancep <expression>)

INSTANCE-ADDRESSP: Returns TRUE if its argument is an instance address,
                   FALSE otherwise.
(instance-addressp <expression>)

INSTANCE-NAMEP: Returns TRUE if its argument is an instance name,
                FALSE otherwise.
(instance-namep <expression>)

INSTANCE-EXISTP: Returns TRUE if the specified instance exists,
                 FALSE otherwise.
(instance-existp <instance-expression>)

END-ENTRY 

INSTANCE_SLOT_FUNCTIONS

 FUNCTION_SUMMARY
  COOL_FUNCTIONS
    INSTANCE_SLOT_FUNCTIONS

The following functions are used to manipulate instance slots. 

DYNAMIC-GET: Returns the value of the specified slot of the active instance.
(dynamic-get <slot-name-expression>)

DYNAMIC-PUT: Sets the value of the specified slot of the active instance.
(put <slot-name-expression> <expression>*)

SLOT-REPLACE$: Allows the replacement of a range of fields in a multifield
               slot value.
(slot-replace$ <instance-expression> <mv-slot-name>
               <range-begin> <range-end> <expression>+)
                 
DIRECT-SLOT-REPLACE$: Allows the replacement of a range of fields in a
                      multifield slot value of the active instance from 
                      within a message-handler.
(direct-slot-replace$ <mv-slot-name> <range-begin> <range-end> <expression>+)
   
SLOT-INSERT$: Allows the insertion of one or more values in a multifield
              slot value.
(slot-insert$ <instance-expression> <mv-slot-name> <index> <expression>+)
                 
DIRECT-SLOT-INSERT$: Allows the insertion of one or more values in a
                     multifield slot value of the active instance from 
                     within a message-handler.
(direct-slot-insert$ <mv-slot-name> <index> <expression>+)
    
SLOT-DELETE$: Allows the deletion of a range of fields in a multifield
             slot value.
(slot-delete$ <instance-expression> <mv-slot-name> <range-begin> <range-end>)
                 
DIRECT-SLOT-DELETE$: Allows the deletion of a range of fields in a multifield
                     slot value of the active instance from within a 
                     message-handler.
(direct-slot-delete$ <mv-slot-name> <range-begin> <range-end>)
             
END-ENTRY 

DEFMODULE_FUNCTIONS

 

The following functions provide ancillary capabilities for the defmodule 
construct.

GET-DEFMODULE-LIST: Returns the list of all defmodules.
(get-defmodule-list)

END-ENTRY 

SEQUENCE_EXPANSION_FUNCTIONS

 
The following functions provide ancillary capabilities for the sequence 
expansion operator.

EXPAND$: When used inside of a function call, expands its arguments
         as separate arguments to the function. The $ operator is 
         merely a shorthand notation for the expand$ function call.
(expand$ <multifield-expression>)

SET-SEQUENCE-OPERATOR-RECOGNITION: Sets the sequence operator recognition
                                   behavior.
(set-sequence-operator-recognition <boolean-expression>)

GET-SEQUENCE-OPERATOR-RECOGNITION: Returns the current value of the sequence 
                                   operator recognition behavior.
(get-sequence-operator-recognition)

END-ENTRY 

COMMAND_SUMMARY

 COMMAND_SUMMARY

This section gives a general overview of the available CLIPS commands.

Subtopics: 
ENVIRONMENT_COMMANDS       DEFFUNCTION_COMMANDS
DEBUGGING_COMMANDS         GENERIC_FUNCTION_COMMANDS
DEFTEMPLATE_COMMANDS       COOL_COMMANDS
FACT_COMMANDS              DEFMODULE_COMMANDS
DEFFACTS_COMMANDS          MEMORY_COMMANDS
DEFRULE_COMMANDS           TEXT_PROCESSING_COMMANDS
AGENDA_COMMANDS            PROFILING_COMMANDS
DEFGLOBAL_COMMANDS
    
END-ENTRY 

ENVIRONMENT_COMMANDS

 COMMAND_SUMMARY
  ENVIRONMENT_COMMANDS
    
The following commands control the CLIPS environment.

LOAD: Loads constructs from a file.
(load <file-name>)

LOAD*: Loads constructs from a file without displaying informational
       messages.
(load* <file-name>)

SAVE: Saves constructs to a file.
(save <file-name>)

BLOAD: Loads a binary image from a file.
(bload <file-name>)

BSAVE: Saves a binary image to a file.
(bsave <file-name>)

CLEAR: Clears the CLIPS environment.
(clear)

EXIT: Exits the CLIPS environment.
(exit)

RESET: Resets the CLIPS environment.
(reset)

BATCH: Executes commands from a file.
(batch <file-name>)

BATCH*: Executes commands from a file. Unlike the batch command,
        evaluates all of the commands in the specified file before 
        returning rather than replacing standard input.
(batch* <file-name>)

OPTIONS: Lists the settings of CLIPS compiler flags.
(options)

SYSTEM: Appends its arguments together to form a command which is
        then sent to the operating system.
(system <lexeme-expression>*)

SET-AUTO-FLOAT-DIVIDEND: Sets the auto-float dividend behaviour.
(set-auto-float-dividend <boolean-expression>)

GET-AUTO-FLOAT-DIVIDEND: Returns the current value of the auto-float 
                         dividend behaviour.
(get-auto-float-dividend)

SET-DYNAMIC-CONSTRAINT-CHECKING: Sets the dynamic constraint checking
                                 behaviour.
(set-dynamic-constraint-checking <boolean-expression>)

GET-DYNAMIC-CONSTRAINT-CHECKING: Returns the current value of the dynamic
                                 constraint checking behaviour.
(get-dynamic-constraint-checking)

SET-STATIC-CONSTRAINT-CHECKING: Sets the static constraint checking
                                behaviour.
(set-static-constraint-checking <boolean-expression>)

GET-STATIC-CONSTRAINT-CHECKING: Returns the current value of the static
                                constraint checking behaviour.
(get-static-constraint-checking)

APROPOS: Displays all symbols currently defined in CLIPS which contain 
         a specified substring
(apropos <lexeme>)

END-ENTRY 

DEBUGGING_COMMANDS

 COMMAND_SUMMARY
  DEBUGGING_COMMANDS
  
The following commands control the CLIPS debugging features.

DRIBBLE-ON: Sends trace information to the specified file.
(dribble-on <file-name>)

DRIBBLE-OFF: Closes the trace file.
(dribble-off)

WATCH: Enables trace information for the specified item.
(watch <watch-item>)
<watch-item> ::= all |
                 compilations | 
                 statistics |
                 focus |
                 messages |
                 deffunctions <deffunction-name>* |
                 globals <global-name>* |
                 rules <rule-name>* |
                 activations <rule-name>* |
                 facts <deftemplate-name>* |
                 instances <class-name>* |
                 slots <class-name>* |
                 message-handlers <handler-spec-1>* [<handler-spec-2>]) |
                 generic-functions <generic-name>* |
                 methods <method-spec-1>* [<method-spec-2>]

<handler-spec-1> ::= <class-name> <handler-name> <handler-type>
<handler-spec-2> ::= <class-name> [<handler-name> [<handler-type>]]

<method-spec-1> ::= <generic-name> <method-index>
<method-spec-2> ::= <generic-name> [<method-index>]

UNWATCH: Disables trace information for the specified item.
(unwatch <watch-item>)

LIST-WATCH-ITEMS: Displays the current state of watch items.
(list-watch-items [<watch-item>])

END-ENTRY 

DEFTEMPLATE_COMMANDS

 COMMAND_SUMMARY
  DEFTEMPLATE_COMMANDS

The following commands manipulate deftemplates.

PPDEFTEMPLATE: Displays the text of a given deftemplate.
(ppdeftemplate <deftemplate-name>)

LIST-DEFTEMPLATES: Displays the list of all deftemplates in the specified
                   module (or the current module if none specified).
(list-deftemplates [<module-name>])

UNDEFTEMPLATE: Deletes a deftemplate.
(undeftemplate <deftemplate-name>)

END-ENTRY 

FACT_COMMANDS

 COMMAND_SUMMARY
  FACT_COMMANDS

The following commands display information about facts.

FACTS: Display the facts in the fact-list.
(facts [<module-name>]
       [<start-integer-expression> 
       [<end-integer-expression> 
       [<max-integer-expression>]]])

LOAD-FACTS: Asserts facts loaded from a file.
(load-facts <file-name>)

SAVE-FACTS: Saves facts to a file.
(save-facts <file-name> [<save-scope> <deftemplate-names>*])
<save-scope> ::= visible | local

DEPENDENCIES: Lists the partial matches from which a fact or 
              instance receives logical support.
(dependencies <fact-or-instance-specifier>)

DEPENDENTS: Lists all facts or instances which receive logical support 
           from a fact or instance.
(dependents <fact-or-instance-specifier>)

SET-FACT-DUPLICATION: Sets the fact duplication behavior.
(set-fact-duplication <boolean-expression>)

GET-FACT-DUPLICATION: Returns the fact duplication behavior.
(get-fact-duplication)

PPFACT: Displays the text of a given fact.
(ppfact <fact-specifier> [<logical-name> [<ignore-defaults-flag>]])

END-ENTRY 

DEFFACTS_COMMANDS

 COMMAND_SUMMARY
  DEFFACTS_COMMANDS

The following commands manipulate deffacts.

PPDEFFACTS: Displays the text of a given deffacts.
(ppdeffacts <deffacts-name>)

LIST-DEFFACTS: Displays the list of all deffacts in the specified
               module (or the current module if none specified).
(list-deffacts [<module-name>])

UNDEFFACTS: Deletes a deffacts.
(undeffacts <deffacts-name>)

END-ENTRY 

DEFRULE_COMMANDS

 COMMAND_SUMMARY
  DEFRULE_COMMANDS

The following commands manipulate defrules.

PPDEFRULE: Displays the text of a given rule.
(ppdefrule <rule-name>)

LIST-DEFRULES: Displays the list of all defrules in the specified
               module (or the current module if none specified).
(list-defrules [<module-name>])

UNDEFRULE: Deletes a defrule.
(undefrule <rule-name>)

MATCHES: Displays the facts which match the patterns of a rule.
(matches <rule-name>)

SET-BREAK: Sets a breakpoint on a rule.
(set-break <rule-name>)

REMOVE-BREAK: Removes a breakpoint on a rule.
(remove-break [<rule-name>])

SHOW-BREAKS: Displays all rules having breakpoints.
(show-breaks [<module-name>])

REFRESH: Places all current activations of a rule on the agenda.
(refresh <rule-name>)

SET-INCREMENTAL-RESET: Sets the incremental reset behavior.
(set-incremental-reset <boolean-expression>)

GET-INCREMENTAL-RESET: Returns the incremental reset behavior.
(get-incremental-reset)

END-ENTRY 

AGENDA_COMMANDS

 COMMAND_SUMMARY
  AGENDA_COMMANDS

The following commands manipulate the agenda.

AGENDA: Displays all activations on the agenda of the specified module.
(agenda [<module-name>])

RUN: Starts execution of rules.  Rules fire until agenda is empty or
     the number of rule firings limit specified by the first argument 
     is reached (infinity if unspecified).
(run [<integer-expression>])

FOCUS: Pushes one or more modules onto the focus stack.
(focus <module-name>+)

HALT: Stops rule execution.
(halt)

SET-STRATEGY: Sets the current conflict resolution strategy.
(set-strategy <strategy>)
<strategy> ::= depth | breadth | simplicity | complexity | lex | mea | random

GET-STRATEGY: Returns the current conflict resolution strategy.
(get-strategy)

LIST-FOCUS-STACK: Lists all module names on the focus stack.
(list-focus-stack)

CLEAR-FOCUS-STACK: Removes all modules from the focus stack.
(clear-focus-stack)

SET-SALIENCE-EVALUATION: Sets the salience evaluation behavior.
(set-salience-evaluation <behavior>)
<behavior> ::= when-defined | when-activated | every-cycle

GET-SALIENCE-EVALUATION: Returns the salience evaluation behavior.
(get-salience-evaluation)

REFRESH-AGENDA: Forces reevaluation of salience of rules on the agenda
                of the specified module.
(refresh-agenda [<module-name>])

END-ENTRY 

DEFGLOBAL_COMMANDS

 COMMAND_SUMMARY
  DEFGLOBAL_COMMANDS
  
The following commands manipulate defglobals.

PPDEFGLOBAL: Displays the text required to define a given global variable.
(ppdefglobal <global-variable-name>)

LIST-DEFGLOBALS: Displays the list of all defglobals in the specified
                 module (or the current module if none specified).
(list-defglobals [<module-name>])

UNDEFGLOBAL: Deletes a global variable.
(undefglobal <global-variable-name>)

SHOWS-DEFGLOBALS: Displays the name and current value of all defglobals 
                  in the specified module (or the current module if none
                  specified).
(show-defglobals [<module-name>])

SET-RESET-GLOBALS: Sets the reset global variables behavior.
(set-reset-globals <boolean-expression>)

GET-RESET-GLOBALS: Returns the reset global variables behavior.
(get-reset-globals)

END-ENTRY 

DEFFUNCTION_COMMANDS

 COMMAND_SUMMARY
  DEFFUNCTION_COMMANDS
 
The following commands manipulate deffunctions.

PPDEFFUNCTION: Displays the text of a given deffunction.
(ppdeffunction <deffunction-name>)

LIST-DEFFUNCTIONS: Displays the list of all deffunctions in the specified
                   module (or the current module if none specified).
(list-deffunctions [<deffunction-name>])

UNDEFFUNCTION: Deletes a deffunction.
(undeffunction <deffunction-name>)

END-ENTRY 

GENERIC_FUNCTION_COMMANDS

 COMMAND_SUMMARY
  GENERIC_FUNCTION_COMMANDS
 
The following commands manipulate generic functions.

PPDEFGENERIC: Displays the text of a given generic function header.
(ppdefgeneric <generic-function-name>)

PPDEFMETHOD: Displays the text of a given method.
(ppdefmethod <generic-function-name> <index>)

LIST-DEFGENERICS: Displays the names of all generic functions in the specified
                  module (or the current module if none specified).
(list-defgenerics [<module-name>])

LIST-DEFMETHODS: Displays a list of generic function methods.
(list-defmethods [<generic-function-name>])

UNDEFGENERIC: Deletes a generic function.
(undefgeneric <generic-function-name>)

UNDEFMETHOD: Deletes a generic function method.
(undefmethod <generic-function-name> <index>)

PREVIEW-GENERIC: Lists all applicable methods for a particular generic
                 function call in order of decreasing precedence.
(preview-generic <generic-function-name> <expression>*)

END-ENTRY 

COOL_COMMANDS

 COMMAND_SUMMARY
  COOL_COMMANDS

The commands manipulating the CLIPS Object-Oriented Language (COOL)
are divided into four categories. 

Subtopics: 
CLASS_COMMANDS                MESSAGE-HANDLER_COMMANDS 
DEFINSTANCES_COMMANDS         INSTANCES_COMMANDS

END-ENTRY 

CLASS_COMMANDS

 COMMAND_SUMMARY
  COOL_COMMANDS
    CLASS_COMMANDS

The following commands manipulate defclasses. 

PPDEFCLASS: Displays the text of a given defclass.
(ppdefclass <class-name>)

LIST-DEFCLASSES: Displays the list of all defclasses in the specified
                 module (or the current module if none specified).
(list-defclasses [<module-name>])

UNDEFCLASS: Deletes a defclass, all its subclasses, and all
            associated instances.
(undefclass <class-name>)

DESCRIBE-CLASS: Provides a verbose description of a class.
(describe-class <class-name>)

BROWSE-CLASSES: Provides a rudimentary display of the inheritance
                relationships between a class and all its subclasses.
(browse-classes [<class-name>])

END-ENTRY 

MESSAGE-HANDLER_COMMANDS

 COMMAND_SUMMARY
  COOL_COMMANDS
    MESSAGE-HANDLER_COMMANDS

The following commands manipulate defmessage-handlers. Note that
<handler-type> is defined as follows:

<handler-type> ::= around | before | primary | after

PPDEFMESSAGE-HANDLER: Displays the text of a given defmessage-handler.
(ppdefmessage-handler <class-name> <handler-name> [<handler-type>])

LIST-DEFMESSAGE-HANDLERS: Displays a list of all (or some) defmessage-
handlers.
(list-defmessage-handlers [<class-name> [<handler-name> [<handler-type>]]])

UNDEFMESSAGE-HANDLER: Deletes a defmessage-handler.
(undefmessage-handler <class-name> <handler-name> [<handler-type>])

PREVIEW-SEND: Displays a list of all the applicable message-handlers for
              a message sent to an instance of a particular class.
(preview-send <class-name> <message-name>)

END-ENTRY 

DEFINSTANCES_COMMANDS

 COMMAND_SUMMARY
  COOL_COMMANDS
    DEFINSTANCES_COMMANDS

The following commands manipulate definstances. 

PPDEFINSTANCES: Displays the text of a given definstances.
(ppdefinstances <definstances-name>)

LIST-DEFINSTANCES: Displays the list of all definstances in the specified
                   module (or the current module if none specified).
(list-definstances [<module-name>])

UNDEFINSTANCES: Deletes a definstances.
(undefinstances <definstances-name>)

END-ENTRY 

INSTANCES_COMMANDS

 COMMAND_SUMMARY
  COOL_COMMANDS
    INSTANCES_COMMANDS

The following commands manipulate instances of user-defined classes. 

INSTANCES: Displays a list of instances.
(instances [<module-name> [<class-name> [inherit]]])

PPINSTANCE: Prints the slots of the active instance when called from 
            within the body of a message-handler.
(ppinstance)

SAVE-INSTANCES: Saves all instances to the specified file.
(save-instances <file-name>)

LOAD-INSTANCES: Loads instances from the specified file.
(load-instances <file-name>)

RESTORE-INSTANCES: Loads instances from the specified file.
(restore-instances <file-name>)

END-ENTRY 

DEFMODULE_COMMANDS

 COMMAND_SUMMARY
  DEFMODULE_COMMANDS

The following commands manipulate defmodules.

PPDEFMODULE: Displays the text of a given defmodule.
(ppdefmodule <defmodule-name>)

LIST-DEFMODULES: Displays the list of all defmodules.
(list-defmodules)

SET-CURRENT-MODULE: Sets the current module.
(set-current-module <module-name>)

GET-CURRENT-MODULE: Returns the current module.
(get-current-module)

END-ENTRY 

MEMORY_COMMANDS

 COMMAND_SUMMARY
  MEMORY_COMMANDS
  
The following commands display CLIPS memory status information.

MEM-USED: Returns the number of bytes of memory CLIPS is using.
(mem-used)

MEM-REQUESTS: Returns the number of times CLIPS has requested memory
              from the operating system.
(mem-requests)

RELEASE-MEM: Releases all free memory held internally by CLIPS to
             the operating system. Returns the amount of memory freed.
(release-mem)

CONSERVE-MEM: Turns on or off the storage of information used for the
              save and pretty-print commands.
(conserve-mem <status>)
<status> ::= on | off

END-ENTRY 

TEXT_PROCESSING_COMMANDS

 COMMAND_SUMMARY
  TEXT_PROCESSING_COMMANDS
  
The following commands can be used by users to maintain their own
information system similar to the help facility.

FETCH: Loads the named file into the internal lookup table.
(fetch <file-name>)

PRINT-REGION: Looks up the specified entry in a particular file which has
              been previously loaded into the lookup table and prints the
              contents of that entry to the specified logical name.
(print-region <logical-name> <lookup-file> <topic-field>*)

GET-REGION: Looks up a specified entry in a particular file which has been 
            loaded previously into the lookup table and returns the contents 
            of that entry as a string.
(get region <file-name> <topic-field>*)

TOSS: Unloads the named file from the internal lookup table.
(toss <file-name>)

END-ENTRY 

PROFILING_COMMANDS

 COMMAND_SUMMARY
  PROFILING_COMMANDS
  
The following commands provide the ability to profile CLIPS programs 
for performance.

SET-PROFILE-PERCENT-THRESHOLD: Sets the minimum percentage of time that 
                               must be spent executing a construct or user 
                               function for it to be displayed by the 
                               profile-info command.
(set-profile-percent-threshold <number in the range 0 to 100>)

GET-PROFILE-PERCENT-THRESHOLD: Returns the current value of the
                               profile percent threshold.
(get-profile-percent-threshold)

PROFILE-RESET: Resets all profiling information currently collected 
               for constructs and user functions.
(profile-reset)

PROFILE-INFO: Displays profiling information currently collected for 
              constructs or user functions.
(profile-info)

PROFILE: Enables/disables profiling of constructs and user 
         functions.
(profile constructs | user-functions | off)

END-ENTRY