Abstract base class for terms that approximate Prolog terms. More...

#include <term.hpp>

Inheritance diagram for pl_search::Term:

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Collaboration diagram for pl_search::Term:

Public Member Functions
virtual TermPtr	dereference ()
	Dereferences the term. The default is to return a shared pointer to term itself.

virtual std::string	repr () const
	Returns a string representation of the term.

virtual bool	isLessThan (Term &t) const =0
	Checks if the term is less than another term.

virtual bool	unifyWith (Engine *engine, TermPtr t)
	A hook for unification of user-defined classes. Only override this method if you want to unify user-defined classes.

virtual bool	is_var ()
	Checks if the term is a variable.

	Term ()
	Default constructor.

virtual	~Term ()
	Virtual destructor for proper cleanup.

Protected Member Functions
virtual bool	isEqualTo (Term &t) const =0
	Checks if the term is equal to another term.

virtual Term *	deref_term ()
	Similar to dereference but returning the "raw" pointer.

Friends
std::ostream &	operator<< (std::ostream &os, const Term &t)
	Overloaded output stream operator for Term.

bool	operator< (Term &t1, Term &t2)
	< operator for Terms.

bool	operator<= (Term &t1, Term &t2)
	<= operator for Term

bool	operator== (Term &t1, Term &t2)
	== operator for Terms

Detailed Description

Abstract base class for terms that approximate Prolog terms.

The Term class provides an interface for Prolog-like terms. It includes methods for dereferencing, binding, resetting, and representing terms as strings. It also includes methods for comparing terms and unifying user-defined classes.

Constructor & Destructor Documentation

◆ Term()

pl_search::Term::Term ( )

inline

Default constructor.

◆ ~Term()

virtual pl_search::Term::~Term ( )

inlinevirtual

Virtual destructor for proper cleanup.

Member Function Documentation

◆ deref_term()

virtual Term * pl_search::Term::deref_term ( )

inlineprotectedvirtual

Similar to dereference but returning the "raw" pointer.

Returns: A pointer to the dereferenced term. WARNING: This should only be used for testing as it returns the raw pointer of a shared_ptr.

Reimplemented in pl_search::PVar, and pl_search::UpdatablePVar.

◆ dereference()

virtual TermPtr pl_search::Term::dereference ( )

inlinevirtual

Dereferences the term. The default is to return a shared pointer to term itself.

Returns: A shared pointer to the dereferenced term.

Reimplemented in pl_search::PVar, and pl_search::UpdatablePVar.

◆ is_var()

virtual bool pl_search::Term::is_var ( )

inlinevirtual

Checks if the term is a variable.

Returns: True if the term is a variable, false otherwise.

Reimplemented in pl_search::PVar.

◆ isEqualTo()

virtual bool pl_search::Term::isEqualTo ( Term & t ) const

protectedpure virtual

Checks if the term is equal to another term.

Parameters

t	The term to compare to.

Returns: True if the terms are equal, false otherwise.

Implemented in pl_search::CList, pl_search::PVar, pl_search::PAtom, pl_search::PFloat, and pl_search::PInt.

◆ isLessThan()

virtual bool pl_search::Term::isLessThan ( Term & t ) const

pure virtual

Checks if the term is less than another term.

Parameters

t	The term to compare to.

Returns: True if the term is less than the other term, false otherwise.

Implemented in pl_search::CList, pl_search::PVar, pl_search::PAtom, pl_search::PFloat, and pl_search::PInt.

◆ repr()

virtual std::string pl_search::Term::repr ( ) const

inlinevirtual

Returns a string representation of the term.

Returns: A string representation of the term.

Reimplemented in pl_search::CList, pl_search::PAtom, pl_search::PFloat, pl_search::PInt, and pl_search::PVar.

◆ unifyWith()

virtual bool pl_search::Term::unifyWith	(	Engine *	engine,
		TermPtr	t
	)

inlinevirtual

A hook for unification of user-defined classes. Only override this method if you want to unify user-defined classes.

Parameters

engine	Pointer to the Engine.
t	The term to unify with.

Returns: True if the unification is successful, false otherwise.

Friends And Related Symbol Documentation

◆ operator<

bool operator<	(	Term &	t1,
		Term &	t2
	)

friend

< operator for Terms.

Approximates the @< operator in Prolog. The ordering is as follows:

pvar < pint, pfloat < patom < clist < user-defined classes;
"older" vars are less than "newer" vars;
patoms are ordered by name;
pints and pfloats are ordered by value;
clists are ordered by the first element, then the second, etc.

Parameters

t1	The first term.
t2	The second term.

Returns: True if the first term is less than the second term, false otherwise.

Parameters

t1	The first term.
t2	The second term.

Returns: True if the first term is less than the second term, false otherwise.

◆ operator<<

std::ostream & operator<<	(	std::ostream &	os,
		const Term &	t
	)

friend

Overloaded output stream operator for Term.

Parameters

os	The output stream.
t	The term to output.

Returns: The output stream.

◆ operator<=

bool operator<=	(	Term &	t1,
		Term &	t2
	)

friend

<= operator for Term

Parameters

t1	The first term.
t2	The second term.

Returns: True if the first term is less than or equal to the second term, false otherwise.

◆ operator==

bool operator==	(	Term &	t1,
		Term &	t2
	)

friend

== operator for Terms

Parameters

t1	The first term.
t2	The second term.

Returns: True if the terms are equal using the appropriate isEqualTo method, false otherwise.

Parameters

t1	The first term.
t2	The second term.

Returns: True if the terms are equal using the isEqualTo method, false otherwise.

The documentation for this class was generated from the following file:

include/pl_search/term.hpp

Public Member Functions

Protected Member Functions

Friends

Detailed Description

Constructor & Destructor Documentation

◆ Term()

◆ ~Term()

Member Function Documentation

◆ deref_term()

◆ dereference()

◆ is_var()

◆ isEqualTo()

◆ isLessThan()

◆ repr()

◆ unifyWith()

Friends And Related Symbol Documentation

◆ operator<

◆ operator<<

◆ operator<=

◆ operator==