Interpretation of wrog use of Operators
- To: mathgroup at smc.vnet.net
- Subject: [mg21344] Interpretation of wrog use of Operators
- From: "Drago Ganic" <drago.ganic at in2.hr>
- Date: Mon, 27 Dec 1999 01:37:52 -0500 (EST)
- Organization: HiNet
- Sender: owner-wri-mathgroup at wolfram.com
Hi !!
I believe that the functions SyntaxQ and SyntaxLength shouldn't return an error message like they do when we use super-, sub-, over- or underscripts with an operator.
In[27]:= SyntaxQ [ "\!\(x\[CirclePlus]\_n y\)" ]
Syntax::"sntxi": "Incomplete expression; more input is needed.\!\(\"\"\)"
Out[27]= False
In[27]:= SyntaxLength [ "\!\(x\[CirclePlus]\_n y\)" ]
Syntax::"sntxi": "Incomplete expression; more input is needed.\!\(\"\"\)"
Out[28]=31
It seems that Mathematica has the problem to interpret the expression
SubscriptBox["\[CirclePlus]", n_ ]
where instead of \[CirclePlus] can be any operator name.
Of course this input is syntactically incorrect, but why the error message when I _just ask_
if it is correct.
In the example of The Mathematica Book 2.8.13
SyntaxLength["1 + 2 + "]
we don't get the error message. I think Mathematica is here inconsistent.
I also don't know how to interpret the return value of the SyntaxLength function because I can't see the FullForm ?
Any comments....
Greetings,
Drago Ganic, Croatia