Question

I have the following code in one of my classes along with checks when the code does not eval:

filterParam="self.recipientMSISDN==tmpBPSS.split('_')[3].split('#')[0] and   self.recipientIMSI==tmpBPSS.split('_')[3].split('#')[1]" 
if eval(filterParam):
   print "Evalled"
else:
   print "Not Evalled\nfilterParam\n'%s'\ntmpBPSS\n'%s'\nself.recipientMSISDN\n'%s'\nself.recipientIMSI\n'%s'" % (filterParam, tmpBPSS, self.recipientMSISDN, self.recipientIMSI)

I am not getting anything to ‘eval’. Here are the results:

Not Evalled
filterParam
'self.recipientMSISDN==tmpBPSS.split('_')[3].split('#')[0] and    self.recipientIMSI==tmpBPSS.split('_')[3].split('#')[1]'
tmpBPSS
'bprm_DAILY_MO_919844000039#892000000'
self.recipientMSISDN
'919844000039'
self.recipientIMSI
'892000000'

So I used the outputs from the above to check the code in a python shell and as you can see the code evalled correctly:

>>> filterParam="recipientMSISDN==tmpBPSS.split('_')[3].split('#')[0] and recipientIMSI==tmpBPSS.split('_')[3].split('#')[1]"
>>> tmpBPSS='bprm_DAILY_MO_919844000039#892000000'
>>> recipientMSISDN='919844000039'
>>> recipientIMSI='892000000'
>>> if eval(filterParam):
...    print "Evalled"
... else:
...    print "Not Evalled"
...
Evalled

Am I off my rocker or what am I missing?

A

Answer 1

Most likely, the type of self.recipientIMSI or self.recipientMSISDN is int, and comparing them with strings returns False. Add this line to see if this is the case:

print type(self.recipientIMSI), type(self.recipientMSISDN)

If not, try checking what the same expression evaluates to without eval.

That said, Are you sure you need to use eval? Usually there’s a way of doing things without eval or exec, which will lead to safer, more maintainable code.