Question

Is there any way to check if a variable (class member or standalone) with specified name is defined? Example:

if "myVar" in myObject.__dict__ : # not an easy way
  print myObject.myVar
else
  print "not defined"

Answer 1

A compact way:

print myObject.myVar if hasattr(myObject, 'myVar') else 'not defined'

htw’s way is more Pythonic, though.

hasattr() is different from x in y.__dict__, though: hasattr() takes inherited class attributes into account, as well as dynamic ones returned from __getattr__, whereas y.__dict__ only contains those objects that are attributes of the y instance.