Reference class property in for loop

Question

I'm new to classes in python and am looking for someone to explain why I'm running into this issue.

I have this class:

class TrackingMeasure:
    Touches = 'Possessions'
    DefensiveImpact = 'Defense'

When I attempt to run this loop:

tracking_refs = ['Touches','DefensiveImpact']
for x in tracking_refs:
    print(TrackingMeasure.x)

I get this error:

AttributeError: type object 'TrackingMeasure' has no attribute 'x'

I'm sure this will be very easy for someone to explain so any help would be greatly appreciated.

Why do you need to do this? It would likely be much better to have an internal dictionary, and just do a lookup of the dictionary. — Carcigenicate, Mar 03 '19 at 23:30

score 1 · Accepted Answer · answered Mar 03 '19 at 23:27

1

You would need to use the internal dict of the class to do that:

print(TrackingMeasure.__dict__[x])

answered Mar 03 '19 at 23:27

Alain T.

score 1 · Answer 2 · answered Mar 03 '19 at 23:30

1

You can use getattr:

tracking_refs = ['Touches','DefensiveImpact']
for x in tracking_refs:
    print(getattr(TrackingMeasure, x))

answered Mar 03 '19 at 23:30

iz_

score 1 · Answer 3 · answered Mar 03 '19 at 23:31

1

getattr(object,string)

this_tm = TrackingMeasure
for x in tracking_refs:
    print(getattr(this_tm,x))

answered Mar 03 '19 at 23:31

Matt Stirling

What is `this_tm` for? – iz_ Mar 03 '19 at 23:32
fair question. I see that my solution creates an instance of the object and your solution references the class – Matt Stirling Mar 04 '19 at 00:08
If you intended to create an instance, you're missing the parentheses. – iz_ Mar 04 '19 at 00:10

3 Answers3