variable 'referenced before assignment' warning, error in all() with .pxd but not .pyx #3477
Description
The following is a standalone example of a problem I've run into trying to accelerate some code:
given allExt.py (takes a set of words and checks if 3rd letter in each is a vowel):
class a3v(object):
def __init__(self, inset):
self.myStrSet = inset # set input word list as an attribute on class instance
def all3Vowels(self): # test if 3rd letter of each word is a vowel
vndx = 2 # local variable for 3rd letter index
inStrSet = self.myStrSet # local variable for class instance word list
if all(
ltr in ("a", "e", "i", "o", "u")
for ltr in (w[vndx] for w in inStrSet)
):
return True
return False
and tst.py:
#!/usr/local/bin/python3
import allExt
a3vL = allExt.a3v(["the", "bright", "flower"])
if a3vL.all3Vowels():
print('yes')
else:
print('no')
The code runs without issue, and fits with examples I have found in the cython docs. However, when augmented with allExt.pxd:
import cython
cdef class a3v:
cdef public list myStrSet
@cython.locals(vndx=int, inStrSet=list, ltr=str)
cpdef bint all3Vowels(self)
Upon compiling as shown I get:
rob@nova-370:01 14:45:55 atmNdx $ cythonize -3 -f -i allExt.py allExt.pxd
[1/1] Cythonizing /Users/rob/sync/rgithub/cython/atmNdx/allExt.py
warning: allExt.py:12:26: local variable 'vndx' referenced before assignment
Error compiling Cython file:
------------------------------------------------------------
...
def all3Vowels(self):
vndx = 2
inStrSet = self.myStrSet
if all(
ltr in ("a", "e", "i", "o", "u")
for ltr in (w[vndx] for w in inStrSet)
^
------------------------------------------------------------
allExt.py:12:41: local variable 'inStrSet' referenced before assignment
Traceback (most recent call last):
OTOH, the equivalent (?) pyx version allExt.pyx:
class a3v(object):
def __init__(self, inset):
self.myStrSet = inset
def all3Vowels(self):
cdef int vndx = 2
cdef list inStrSet = self.myStrSet
cdef str ltr
if all(
ltr in ("a", "e", "i", "o", "u")
for ltr in (w[vndx] for w in inStrSet)
):
return True
return False
compiles and runs without issue.
Have I missed something in the docs or some other simple issue?
Thank you.