Re: [Jython-users] Supporting + on Java objects

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As the one that asked Anythony about this (mis?)feature on the 
jpublish list, I'd like to add my support to his request. I'd have 
done it directly except that I'm so new to python that I'd thought 
this was my fault.

PS: The token (+ vs , vs nothing) isn't important. What *is* is that 
the result winds up as a string, not array, tuple, etc.

PPS: Probably harder, supporting expansion of variables within 
strings ala' perl would immediately make python a favorite. The 
${variable}s workaround that was offered here earlier is a bit 
obscure for heavily used stuff like expanding variable information 
into html template files.

See http://virtualschool.edu/jwaa under Mls (multi line 
preprocessor), velocity, or JSP/ASP for workarounds to the same 
problem in Java. This really "should" be supported by the language, 
not outside as in mls, velocity, or jsp. Like this:

title = "my title"
print '''
<html>
	<head>
		<title>$title</title>
	</head>
</html>
'''

Ideally, this should work for any expression (variables, subroutine 
calls, arrays, tuples, etc). As I recall, perl didn't do all of these 
right. Don't recall exactly; I haven't used perl in some years.

At 1:23 PM -0500 3/26/02, Anthony Eden wrote:
>Currently, in Jython, using any arbitrary Java object aside from a 
>java.lang.String, the following fails:
>
>   print "text" + obj
>
>With the message: TypeError: __add__ nor __radd__ defined for these operands
>
>But the following works:
>
>   print "test", obj
>
>Would the Jython implementers consider modifying the PyJavaInstance 
>class with something similar to:
>
>     public PyObject __add__(PyObject object) {
>    	return __str__ + object.__str__();
>     }
>
>So that the + notation as used in Java works properly?  I am not 
>sure if the code I provided above is correct as I am
>not intimately familiar with the Jython source.  I am also not sure 
>if this has been discussed before: the mailing list
>archives provided at the Jython.org site do not have search 
>facilities (AFAICT) and I was unable to find anything about
>it in my mail application (back to 7/21/2001), so I apologize ahead 
>of time if it has.
>
>Sincerely,
>Anthony Eden
>
>
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>Jython-users mailing list
>Jyt...@li...
>https://lists.sourceforge.net/lists/listinfo/jython-users

-- 
Brad Cox, PhD; bc...@vi... 703 361 4751
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