May i customize basic operator (such as 1==3)?

[Carl Friedrich Bolz]

kanchy kang wrote:
> many people write test cases with python scripts.
> in these test scripts, there are many validation statements,
> for example, in unittest, failUnless(a == b),(a/b may be stringType or 
> intType...)
> 
> during running test scripts, if there is one exception raised from 
> failUnless, i still do not know a =?, b= ?... i have to add one statment 
> "print a" or "print b" again...
> 
> as i know, there are many validation statements if using python as one 
> test tool...
> i think my suggestion or requirement may benefit users greatly...
> 

you could use the py.test testing framework 
(http://codespeak.net/py/current/doc/test.html), which tries to print 
useful information if a test fails. So if your test contains

assert a == b

and this is False, it will print the values of a and b. For example the test

def test_fail():
     a = 1
     b = 2
     assert a == b

would result in the following failure:


     def test_fail():
         a = 1
         b = 2
E       assert a == b
 >       assert 1 == 2


This has the drawback that your expressions need to be side-effect free 
(because they will be re-evaluated) but it is quite useful.

Cheers,

Carl Friedrich Bolz