mapnik/mapnik — Issue #933: evaluating an expression adds attribute name to feature
Author: springmeyer
Created: 2011-10-27 01:16:03+00:00
State: open

Perhaps this is just a bug with the python object, but sure is odd:

```python
>>> from mapnik2 import Expression, Feature
>>> f = Feature(1)
>>> f['name'] = 'a'
>>> print f
feature (
id:1
name:a
)

>>> Expression("[name]='a'").evaluate(f)
True # good
>>> print f
feature (
id:1
name:a
) # all normal
>>> Expression("[this does not exist ]='a'").evaluate(f)
False
>>> print f
feature (
id:1
name:a
thisdoesnotexist:
)

# woah - why is 'thisdoesnotexist' showing up?
```