Common error messages

'Wrapper' object is not callable

Additional brackets when calling nut:

>>> from nutsflow import *
>>> greater0 = Filter(lambda x : x > 0)
>>> [2, -1, 3] >> greater0() >> Collect()  
...
TypeError: 'Wrapper' object is not callable

Should be:

>>> greater0 = Filter(lambda x : x > 0)
>>> [2, -1, 3] >> greater0 >> Collect()
[2, 3]

unsupported operand type(s) for >>

Missing brackets when calling nut:

>>> Greater0 = nut_filter(lambda x: x > 0)
>>> [2, -1, 3] >> Greater0 >> Collect()  
...
TypeError: unsupported operand type(s) for >>: 'list' and 'type'

Should be:

>>> Greater0 = nut_filter(lambda x: x > 0)
>>> [2, -1, 3] >> Greater0() >> Collect()
[2, 3]

name '_' is not defined

Typically encountered when using _ without importing it. Example:

>>> from nutsflow import *
>>> [2, -1, 3] >> Filter(_ > 0) >> Collect()  
...
NameError: name '_' is not defined

Since _ is a common name for place-holder variables the explicit import of _ is required:

>>> from nutsflow import *
>>> from nutsflow import _
>>> [2, -1, 3] >> Filter(_ > 0) >> Collect()
[2, 3]