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SetDelayed (:=)Clear

Unset

FilledSmallSquarelhs =. removes any rules defined for lhs.

FilledSmallSquare Rules are removed only when their left-hand sides are identical to lhs, and the tests in Condition given on the right-hand side are also identical.

FilledSmallSquare See The Mathematica Book: Section 1.4.2, Section 2.4.3 and Section A.5.4.

FilledSmallSquare See also: Clear, TagUnset.

Further Examples

SetDelayed (:=)Clear