Jess Value Functions

List of value functions that can be executed by Jess.


8.47. (evenp <expression>)

Package:
PredFunctions
Arguments:
One numeric expression
Returns:
Boolean
Description:
Returns TRUE for even numbers; otherwise, returns FALSE. Results with non-integers may be unpredictable.

8.51. (external-addressp <expression>)

Package:
PredFunctions
Arguments:
One expression
Returns:
Boolean
Description:
Returns TRUE or FALSE as the given expression is an external-address.

8.58. (floatp <expression>)

Package:
PredFunctions
Arguments:
One numeric expression
Returns:
Boolean
Description:
Returns TRUE for floats; otherwise, returns FALSE.

8.73. (integerp <expression>)

Package:
PredFunctions
Arguments:
One expression
Returns:
Boolean
Description:
Returns TRUE for integers; otherwise, returns FALSE.

8.78. (lexemep <expression>)

Package:
PredFunctions
Arguments:
Any expression
Returns:
Boolean
Description:
Returns TRUE for symbols and strings; otherwise, returns FALSE.

8.86. (longp <expression>)

Package:
MiscFunctions
Arguments:
One expression
Returns:
Boolean
Description:
Returns TRUE if the expression is of type RU.LONG; FALSE otherwise.

8.94. (multifieldp <expression>)

Package:
PredFunctions
Arguments:
Any value
Returns:
Boolean
Description:
Returns TRUE for multifield values; otherwise, returns FALSE.

8.99. (numberp <expression>)

Package:
PredFunctions
Arguments:
One expression
Returns:
Boolean
Description:
Returns TRUE for numbers; otherwise, returns FALSE.

8.100. (oddp <integer-expression>)

Package:
PredFunctions
Arguments:
One integer expression
Returns:
Boolean
Description:
Returns TRUE for odd numbers; otherwise, returns FALSE; see evenp.

8.144. (stringp <expression>)

Package:
PredFunctions
Arguments:
One expression
Returns:
Boolean
Description:
Returns TRUE for strings; otherwise, returns FALSE.

8.147. (subsetp <multifield-expression> <multifield-expression>)

Package:
MultiFunctions
Arguments:
Two multifields
Returns:
Boolean
Description:
Returns TRUE if the first argument is a subset of the second (i.e., all the elements of the first multifield appear in the second multifield); otherwise, returns FALSE.

8.149. (symbolp <expression>)

Package:
PredFunctions
Arguments:
One expression
Returns:
Boolean
Description:
Returns TRUE for symbols; otherwise, returns FALSE.