org.algernon.datatype
Class BindingSet

java.lang.Object
  org.jatha.dynatype.StandardLispValue
      org.jatha.dynatype.StandardLispConsOrNil
          org.algernon.datatype.BindingSet

All Implemented Interfaces:

Comparable, LispConsOrNil, LispValue

public class BindingSet

extends StandardLispConsOrNil

This is a set of BindingLists.

Field Summary

private Algernon	f_algy
protected ArrayList	f_bindings
LispValue	FAILED

Fields inherited from class org.jatha.dynatype.StandardLispValue

f_lisp

Constructor Summary

BindingSet(Algernon algy)
Create a new BindingSet.

BindingSet(Algernon algy, BindingList bl)
Create a new BindingSet containing one binding list.

Method Summary

void	addList(BindingList newList) Adds a new list to the binding set.
LispValue	bind(LispValue var, LispValue env, LispValue term)
int	bindingsCount() Returns the number of bindings across all binding lists in the set.
protected static LispValue	bindingTerm(LispValue binding)
protected static LispValue	bindingVar(LispValue binding)
void	clear() Removes all entries from the BindingSet.
protected LispValue	dereferenceExpression(LispValue term, LispValue env, LispValue patEnv) Follows bindings to a non-variable or unbound variable.
protected static LispValue	dereferencePattern(LispValue pattern, LispValue patEnv) Follows bindings to a non-variable or unbound variable.
BindingList	getEntry(int index) Return the nth BindingList in the given register, where the topmost item is entry number zero.
BindingList	getRandomBindingList() Returns a random binding list from the set.
boolean	hasSingleBinding(LispValue var) Returns true if the given variable has one and only one binding in this binding set.
boolean	isEmpty() Returns true if this binding set contains no bindings.
Iterator	iterator() Returns an iterator over the BindingSet.
BindingSet	merge(BindingSet otherSet) Merges two binding sets and returns a new one.
LispValue	pop() Removes the first BindingList and returns it.
BindingSet	push(BindingList newList) Pushes the new BindingList onto the BindingSet.
int	size() Returns the number of binding lists in this binding set.
String	toString()
LispValue	unify(LispValue pattern, LispValue expression) Unifies the unbound clause with the bound clauses (data) and returns a binding list containing the bindings derived from unification.
protected LispValue	unifyAux(LispValue pattern, LispValue patEnv, LispValue expression, LispValue expEnv)
BindingSet	unmerge(LispValue countedVariable) Takes a merged binding set and undoes the combinatorial merge, returning a binding set which represents the previous version of the input set before the merge.

Methods inherited from class org.jatha.dynatype.StandardLispConsOrNil

basic_consp, basic_listp, butlast, elt, length, listp, nconc, nreverse, position, reverse

Methods inherited from class org.jatha.dynatype.StandardLispValue

abs, acos, add, adjustSpecialCount, append, apply, apropos_print, asin, assoc, atan, atan2, atom, basic_atom, basic_bignump, basic_constantp, basic_floatp, basic_foreignp, basic_functionp, basic_integerp, basic_keywordp, basic_length, basic_macrop, basic_null, basic_numberp, basic_stringp, basic_symbolp, bignump, boundp, car, cdr, ceiling, characterp, clrhash, compareTo, concatenate, consp, constantp, contains, copy_list, copy, cos, cot, csc, degreesToRadians, divide, eighth, elt, eq, eql, equal, equalNumeric, factorial, fboundp, fifth, first, floatp, floor, fourth, funcall, functionp, get_specialCount, gethash, gethash, getLisp, greaterThan, greaterThanOrEqual, hash_table_count, hash_table_rehash_size, hash_table_rehash_threshold, hash_table_size, hash_table_test, hashtablep, integerp, internal_getName, internal_prin1_as_cdr, internal_prin1, internal_princ_as_cdr, internal_princ, internal_print_as_cdr, internal_print, keywordp, last, lessThan, lessThanOrEqual, lisp_null, list, max, member, min, multiply, negate, neql, ninth, nstringCapitalize, nstringDowncase, nstringUpcase, numberp, prin1, princ, print, push, radiansToDegrees, rassoc, reciprocal, remhash, remove, rest, rplaca, rplacd, sec, second, set_special, setf_gethash, setf_symbol_function, setf_symbol_plist, setf_symbol_value, setLisp, setPackage, setq, seventh, sin, sixth, specialP, sqrt, string, stringCapitalize, stringDowncase, stringEndsWith, stringEq, stringEqual, stringGreaterP, stringGreaterThan, stringGreaterThanOrEqual, stringLeftTrim, stringLeftTrim, stringLessP, stringLessThan, stringLessThanOrEqual, stringNeq, stringNotGreaterP, stringNotLessP, stringp, stringRightTrim, stringRightTrim, stringStartsWith, stringTrim, stringTrim, stringUpcase, subst, substring, substring, subtract, symbol_function, symbol_name, symbol_package, symbol_plist, symbol_value, symbolp, tan, tenth, third, toCollection, toJava, toJava, toString, toStringAsCdr_internal, toStringAsCdr, toStringShort, toStringShort, toStringSimple, type_of, typep, zerop

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.jatha.dynatype.LispValue

abs, acos, add, adjustSpecialCount, append, apply, apropos_print, asin, assoc, atan, atan2, atom, basic_atom, basic_bignump, basic_constantp, basic_floatp, basic_foreignp, basic_functionp, basic_integerp, basic_keywordp, basic_length, basic_macrop, basic_null, basic_numberp, basic_stringp, basic_symbolp, bignump, boundp, car, cdr, ceiling, characterp, clrhash, compareTo, concatenate, consp, constantp, contains, copy_list, copy, cos, cot, csc, degreesToRadians, divide, eighth, elt, eq, eql, equal, equalNumeric, factorial, fboundp, fifth, first, floatp, floor, fourth, funcall, functionp, get_specialCount, gethash, gethash, getLisp, greaterThan, greaterThanOrEqual, hash_table_count, hash_table_rehash_size, hash_table_rehash_threshold, hash_table_size, hash_table_test, hashtablep, integerp, internal_getName, internal_prin1_as_cdr, internal_prin1, internal_princ_as_cdr, internal_princ, internal_print_as_cdr, internal_print, keywordp, last, lessThan, lessThanOrEqual, lisp_null, list, max, member, min, multiply, negate, neql, ninth, nstringCapitalize, nstringDowncase, nstringUpcase, numberp, prin1, princ, print, push, radiansToDegrees, rassoc, reciprocal, remhash, remove, rest, rplaca, rplacd, sec, second, set_special, setf_gethash, setf_symbol_function, setf_symbol_plist, setf_symbol_value, setLisp, setPackage, setq, seventh, sin, sixth, specialP, sqrt, string, stringCapitalize, stringDowncase, stringEndsWith, stringEq, stringEqual, stringGreaterP, stringGreaterThan, stringGreaterThanOrEqual, stringLeftTrim, stringLeftTrim, stringLessP, stringLessThan, stringLessThanOrEqual, stringNeq, stringNotGreaterP, stringNotLessP, stringp, stringRightTrim, stringRightTrim, stringStartsWith, stringTrim, stringTrim, stringUpcase, subst, substring, substring, subtract, symbol_function, symbol_name, symbol_package, symbol_plist, symbol_value, symbolp, tan, tenth, third, toCollection, toJava, toJava, toString, toStringAsCdr_internal, toStringAsCdr, toStringShort, toStringShort, toStringSimple, type_of, typep, zerop

Field Detail

FAILED

public LispValue FAILED

f_bindings

protected ArrayList f_bindings

f_algy

private Algernon f_algy

Constructor Detail

BindingSet

public BindingSet(Algernon algy)

Create a new BindingSet.

BindingSet

public BindingSet(Algernon algy,
                  BindingList bl)

Create a new BindingSet containing one binding list.

Method Detail

toString

public String toString()

addList

public void addList(BindingList newList)

Adds a new list to the binding set.

getEntry

public BindingList getEntry(int index)

Return the nth BindingList in the given register, where the topmost item is entry number zero. If the index given is greater than the number of items in the register, null is returned. This value can always be coerced to BindingList.

merge

public BindingSet merge(BindingSet otherSet)

Merges two binding sets and returns a new one.

unify

public LispValue unify(LispValue pattern,
                       LispValue expression)

Unifies the unbound clause with the bound clauses (data) and returns a binding list containing the bindings derived from unification. Returns the symbol :FAILED if the bindings failed.

unifyAux

protected LispValue unifyAux(LispValue pattern,
                             LispValue patEnv,
                             LispValue expression,
                             LispValue expEnv)

bind

public LispValue bind(LispValue var,
                      LispValue env,
                      LispValue term)

dereferenceExpression

protected LispValue dereferenceExpression(LispValue term,
                                          LispValue env,
                                          LispValue patEnv)

Follows bindings to a non-variable or unbound variable. Returns the final term and its environment.

dereferencePattern

protected static LispValue dereferencePattern(LispValue pattern,
                                              LispValue patEnv)

Follows bindings to a non-variable or unbound variable. Returns the final term. (We know that the term's environment is still *PAT-ENV*, if it is a variable, because no variable in *PAT-ENV* is ever bound to a variable in *EXP-ENV*.)

bindingTerm

protected static LispValue bindingTerm(LispValue binding)

bindingVar

protected static LispValue bindingVar(LispValue binding)

getRandomBindingList

public BindingList getRandomBindingList()

Returns a random binding list from the set.

pop

public LispValue pop()

Removes the first BindingList and returns it. The value can be coerced to BindingList. Returns null if there are not enough BindingLists.

hasSingleBinding

public boolean hasSingleBinding(LispValue var)

Returns true if the given variable has one and only one binding in this binding set.

push

public BindingSet push(BindingList newList)

Pushes the new BindingList onto the BindingSet.

size

public int size()

Returns the number of binding lists in this binding set.

clear

public void clear()

Removes all entries from the BindingSet.

iterator

public Iterator iterator()

Returns an iterator over the BindingSet. Each element of the iteration is a BindingList.

isEmpty

public boolean isEmpty()

Returns true if this binding set contains no bindings.

bindingsCount

public int bindingsCount()

Returns the number of bindings across all binding lists in the set.

unmerge

public BindingSet unmerge(LispValue countedVariable)

Takes a merged binding set and undoes the combinatorial merge, returning a binding set which represents the previous version of the input set before the merge. Destructively modifies the list.

Parameters:

countedVariable -