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[IDV #HNT-802608]: Request to change jython "shell" utilities

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  • Subject: [IDV #HNT-802608]: Request to change jython "shell" utilities
  • Date: Wed, 11 May 2011 14:07:55 -0600
> Hi Yuan & Julien --
> 
> Related to the explicit testing for "null" in the Java code, we also
> found that in a few places in 3 of the .py files (shell.py, grid.py
> and maps.py) there are statements like:
> 
> a = getSomething()
> if (a == None) doSomething...
> 
> The problem here, as related to the one you just fixed in Java, is
> that if "a" is a class and has an "equals" or "__eq__" (or __ne__)
> method, this will be called when the
> "if (a == None") is done.  The Jython code should be changed to
> 
> if (a is None) doSomething...
> 
> or
> 
> if (a is not None) doSomething...
> 
> This form does not result in the interpreter calling the Java method,
> and so is "safe" in this situation (when testing against "None").
> 
> I have attached a zip file with updates to the 3 py files I mentioned
> above.  Hopefully, you will be able to have time to check these and
> update the IDV resource/python/ files
> accordingly.
> 
> Thanks.
> 
> tom

Hi Tom,
   I checked in the changes, thanks for these updates.

Yuan
> 
> --
> Tom Whittaker
> University of Wisconsin-Madison
> Space Science & Engineering Center (SSEC)
> Cooperative Institute for Meteorological Satellite Studies (CIMSS)
> 1225 W. Dayton Street
> Madison, WI  53706  USA
> ph: +1 608 262 2759
> 
> 


Ticket Details
===================
Ticket ID: HNT-802608
Department: Support IDV
Priority: Normal
Status: Closed