x <==>= y
The object <==>= is a keyword.
This operator may be used as a binary operator in an expression like x<==>=y. The user may install a method for handling such expressions with code such as
X <==>= (x,y) -> ...
where X is the class of x.
The source of this document is in /build/reproducible-path/macaulay2-1.25.05+ds/M2/Macaulay2/packages/Macaulay2Doc/operators/augmented_assignment.m2:39:0.