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UpSetDelayed

  • lhs ^:= rhs assigns rhs to be the delayed value of lhs, and associates the assignment with symbols that occur at level one in lhs.
  • See notes for UpSet and SetDelayed.
  • See the Mathematica book: Section 2.4.10Section 2.4.10.

    Further Examples

    This defines an upvalue for f with respect to Plus.

    In[1]:=

    The upvalue can now be applied.

    In[2]:=

    Out[2]=