[Python-Dev] Exceptions in LOAD_GLOBAL and LOAD_NAME

Feb. 23, 2012

      The code below causes different behaviour for LOAD_GLOBAL and LOAD_NAME.
Which is correct?
Should exceptions raised in the equality test be converted to a 
NameError or just propogated?

Cheers,
Mark.

-------------------------------------
import sys

class S(str):
     pass

def eq_except(self, other):
     if isinstance(other, str):
         raise TypeError("Cannot compare S and str")

globals()[S("a")] = 0

S.__eq__ = eq_except

def f():
     print(a)

try:
     f()
except:
     print(sys.exc_info()[1])

try:
     print(a)
except:
     print(sys.exc_info()[1])
----------------------------------

Output:

TypeError('Cannot compare S and str',)
NameError("name 'a' is not defined",)

[Python-Dev] Exceptions in LOAD_GLOBAL and LOAD_NAME

Mark Shannon