Constant

interface Constant: Term, Any

Fields

Name Description
open isConstant: Boolean

Checks whether the current term is a constant, i.e., either an atom or a number. This method is guaranteed to return true if and only if the current term is an instance of Constant.

abstract value: Any

Methods

freshCopy

abstract fun freshCopy(): Constant

Returns a fresh copy of this Term, that is, an instance of Term which is equal to the current one in any aspect, except variables directly or indirectly contained into this Term, which are refreshed. This means that it could return itself, if no variable is present (ground term), or a new Term with freshly generated variables.

Variables are refreshed consistently, meaning that, if more variables exists within this Term having the same name, all fresh copies of such variables will have the same complete name.

Example: "f(X, g(X))".freshCopy() returns something like "f(X_1, g(X_1))" instead of "f(X_1, g(X_2))"

Notice that, if the current term is ground, the same object may be returned as a result by this method.

ReturnValue

Name Description
Constant

a fresh copy of the current term which is different because variables are consistently renamed

freshCopy

abstract fun freshCopy(scope: Scope): Constant

Returns a fresh copy of this Term, similarly to freshCopy, possibly reusing variables from the provided scope, if any

Parameters

Name Description
scope: Scope

the Scope containing variables to be used in copying

ReturnValue

Name Description
Constant

a fresh copy of the current term which is different because variables are consistently renamed

asConstant

open fun asConstant(): Constant

Casts the current Term to Constant, if possible, or returns null otherwise

ReturnValue

Name Description
Constant

the current Term, casted to Constant, or null, if the current term is not an instance of Constant

Extensions

toClause

fun Term.toClause(source: Any?, line: Int, column: Int): Clause

Receiver

Name Description
Term

Parameters

Name Description
source: Any?
line: Int
column: Int

ReturnValue

Name Description
Clause

unfoldGoals

fun Term.unfoldGoals(): Sequence<Term>

Receiver

Name Description
Term

ReturnValue

Name Description
Sequence<Term>

toGoals

fun Term.toGoals(): Cursor<Term>

Receiver

Name Description
Term

ReturnValue

Name Description
Cursor<Term>

isWellFormed

fun Term.isWellFormed(): Boolean

Check whether the receiver term is a well-formed predication

Receiver

Name Description
Term

ReturnValue

Name Description
Boolean

prepareForExecutionAsGoal

fun Term.prepareForExecutionAsGoal(): Struct

Prepares the receiver Goal for execution

For example, the goal A is transformed, after preparation for execution, as the Term: call(A)

Receiver

Name Description
Term

ReturnValue

Name Description
Struct

evalAsExpression

fun Term.evalAsExpression(request: Request<*>, index: Int?): Term

Receiver

Name Description
Term

Parameters

Name Description
request: Request<*>
index: Int?

ReturnValue

Name Description
Term

evalAsArithmeticExpression

fun Term.evalAsArithmeticExpression(request: Request<*>, index: Int?): Numeric

Receiver

Name Description
Term

Parameters

Name Description
request: Request<*>
index: Int?

ReturnValue

Name Description
Numeric

eq

infix fun Term.eq(that: Term): Equation

Creates an equation with this and that terms

Receiver

Name Description
Term

Parameters

Name Description
that: Term

ReturnValue

Name Description
Equation