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RE: Precedence of Infix Operator

• To: mathgroup at smc.vnet.net
• Subject: [mg84088] RE: [mg84073] Precedence of Infix Operator
• From: "David Park" <djmpark at comcast.net>
• Date: Mon, 10 Dec 2007 04:33:08 -0500 (EST)
• References: <200712091134.GAA03937@smc.vnet.net> <4165723.1197238586697.JavaMail.root@m41>

Thanks again Carl.

I had a faint recollection there was such a file and actually spent about an
hour looking through system .tr files - but not that one of course!

However, I have a difficulty with this solution. If I were to include this
as part of a package I think that users would be justifiably reluctant to
copy my new UnicodeCharacters.tr into the Wolfram system files, even if I
also supplied a saved version. And also I wouldn't want this as a permanent
change.

Mathematica supplies a number of infix operators that have no definitions.
If they have no definitions, why should it be assumed that they would have a
fixed precedence level? Specifying a precedence level is really a very
fundamental part of implementing a new operator. Would it be that difficult
to allow these operators to take a PrecedenceLevel option so that a user
could set this value for his or her local needs? I believe this would be a
very useful feature for Mathematica.


David Park
djmpark at comcast.net
http://home.comcast.net/~djmpark 


From: Carl Woll [mailto:carlw at wolfram.com] 

David Park wrote:

>I would like to use some less common infix operator, such as Colon or 
>VerticalBar, but give it a precedence on input greater than Times. Is there

>a way to do this?
>
>  
>
First, save a copy of UnicodeCharacters.tr. Then, open it and change the 
precedence of \[Colon] or \[VerticalBar] to something larger than that 
of \[Times] (520).

Carl Woll
Wolfram Research

• References:
  • Precedence of Infix Operator
    • From: "David Park" <djmpark@comcast.net>