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TagSetDelayedUpSet (^=)

TagUnset

FilledSmallSquaref/: lhs =. removes any rules defined for lhs, associated with the symbol f.

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

FilledSmallSquare See The Mathematica Book: Section A.2.7 and Section A.5.4.

FilledSmallSquare See also: Clear, Unset.

Further Examples

TagSetDelayedUpSet (^=)