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User defined aliases

  • To: mathgroup at
  • Subject: User defined aliases
  • From: Markus Lautenbacher <Markus.Lautenbacher at>
  • Date: Mon, 12 Nov 90 22:56:30 +0100

Hi mathgroup readers,

perhaps some of you can give me a little advice on the following
I have defined a function `OperatorProduct' which I want to transform
via pattern matching in something else on the right hand side of
several transformation rules, e.g.

OperatorProduct[a_,b_] := f[a,b]

(What is actually on the right hand side doesn't matter for the
problem I describe here.)  Now, `OperatorProduct' is a quite
descriptive but also long name and I wanted to have something shorter.
Since `Alias[]' tells you that `*' is just an alias for `Times' I
tried `<>::=OperatorProduct' (I used `<>' is still unused) in order to
allow for typing just `a <> b' instead of `OperatorProduct[a,b]'.

However, Mathematica refused to accept this alias. Trying several
versions like `<>::=~OperatorProduct~" and likewise forms didn't work
either. Somehow Mathematica seems to resolve `<>' to the mathematical
`less' and `greater' relations instead of a new combined symbol `<>'.
What worked was `op::=OperatorProduct' with a usage like e.g. 
`a ~op~ b' but that is not excatly what I wanted.

Does anybody know whether aliases like `*' are hard wired in
Mathematica or is there a simple way to get my `<>' to work.  The
important point is that I want to define a new kind of valid _input_
format for the user defined function `OperatorProduct'. If it just
were for formatting the output of `OperatorProduct' the `Infix'
function (p. 278 MathBook) would of course do the job.

Thanks in advance,

#   MARKUS E. LAUTENBACHER,                                               #
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