check python version to solve unichr not defined problem

[shivareddyiirs]

Fix #161
If unicode does not throw exception , then check the python version so that this problem can be solved.

[shivareddyiirs]

@ukanga
Thanks for your comment. if this pull request is merged, it would be great help for develpers using pyxform in python 3 but having similar issue #161.

[ukanga]

I think QGIS 3 might be implementing the unicode() function in python 3 or it gets injected somehow. On python 3 every version I have tested, if unicode() results in the NameError exception, so will the unichr() function. This may be the reason, despite us testing in python 2.7 to 3.6 on windows we still don't get this issue.

try:
    unicode("str")
except NameError:
    # Python 3 only should go through here
    unicode = str
    basestring = str
    unichr = chr
else:
    # python 2 only should go through here
    unicode = unicode
    basestring = basestring
    # if for whatever reason python 3 is here 
    # it means unichr was not give the same treatment as unicode and basestring above
    # probably do another try except
    try:
        unichr = unichr
    except NameError:
        unichr = chr

Could you validate that this only happens when using QGIS?

I am going to try and replicate the #161 exception on my end once I get a hold of a windows VM and install qgis on it.

[shivareddyiirs]

Yes, it only happen in QGIS. Your idea of using another try except also seems good and simple. but I would suggest putting whole 'else' block in 'try' to be safe. Thanks & Regards Shiva Reddy K. Scientist/Engineer 'SC' Indian Institute of Remote Sensing, Indian Space Research Organisation Department of Space 4-Kalidas Road Dehradun mobile: 8791806093

…

On Thu, Mar 8, 2018 at 1:57 AM, ukanga ***@***.***> wrote: I think QGIS 3 might be implementing the unicode() function in python 3 or it gets injected somehow. On python 3 every version I have tested, if unicode() results in the NameError exception, so will the unichr() function. This may be the reason, despite us testing in python 2.7 to 3.6 on windows we still don't get this issue. try: unicode("str")except NameError: # Python 3 only should go through here unicode = str basestring = str unichr = chrelse: # python 2 only should go through here unicode = unicode basestring = basestring # if for whatever reason python 3 is here # it means unichr was not give the same treatment as unicode and basestring above # probably do another try except try: unichr = unichr except NameError: unichr = chr Could you validate that this only happens when using QGIS? I am going to try and replicate the #161 <#161> exception on my end once I get a hold of a windows VM and install qgis on it. — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#179 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AFZECMq-pNFenuW65V7Rd8sj5iOXG4flks5tcELJgaJpZM4SeUiI> .