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Function TREE-EQUAL

Syntax

  • tree-equal tree-1 tree-2 &key test test-notgeneralized-boolean

Arguments and Values

Description

tree-equal tests whether two trees are of the same shape and have the same leaves. tree-equal returns true if tree-1 and tree-2 are both atoms and satisfy the test, or if they are both conses and the car of tree-1 is tree-equal to the car of tree-2 and the cdr of tree-1 is tree-equal to the cdr of tree-2. Otherwise, tree-equal returns false.

tree-equal recursively compares conses but not any other objects that have components.

The first argument to the :test or :test-not function is tree-1 or a car or cdr of tree-1; the second argument is tree-2 or a car or cdr of tree-2.

Examples

(defparameter *tree-1* '(1 (1 2))) → (1 (1 2))

*TREE-1*

(defparameter *tree-2* '(1 (1 2))) → (1 (1 2))

*TREE-2*

(tree-equal *tree-1* *tree-2*)

true

(eql *tree-1* *tree-2*)

false

(setf *tree-1* '('a ('b 'c)))

('a ('b 'c)) ; ≡ ((QUOTE A) ((QUOTE B) (QUOTE C)))

(setf *tree-2* '('a ('b 'c)))

('a ('b 'c)) ; ≡ ((QUOTE A) ((QUOTE B) (QUOTE C)))

(tree-equal *tree-1* *tree-2* :test #'eq)

true

Side Effects

None.

Affected By

None.

Exceptional Situations

The consequences are undefined if both tree-1 and tree-2 are circular.

See Also

Function EQUAL, {\secref\TraversalRules}

Example Implementation

To be done.

Notes

The :test-not parameter is deprecated.

\issue{DOTTED-LIST-ARGUMENTS:CLARIFY} \issue{MAPPING-DESTRUCTIVE-INTERACTION:EXPLICITLY-VAGUE} \issue{TEST-NOT-IF-NOT:FLUSH-ALL}