About getattr()

[Jm lists]

Hello,

Since I can write the statement like:
Test whether a path is a directory

Why do I still need the getattr() func as below?
Test whether a path is a directory

Thanks!

 

[Leif K-Brooks]

Since I can write the statement like:

Test whether a path is a directory

Why do I still need the getattr() func as below?

Test whether a path is a directory

You don't. getattr() is only useful when the attribute name is
determined at runtime.

 

[Samuel Karl Peterson]

Hello,

Since I can write the statement like:

Test whether a path is a directory

Why do I still need the getattr() func as below?

Test whether a path is a directory

getattr lets you lookup an attribute given a string, so the attribute
wouldn't have to be hardcoded in your program, it could come from a
file, or from user input.

 

[Duncan Booth]

You don't.
Correct

getattr() is only useful when the attribute name is
determined at runtime.

getattr() is useful in at least 2 other situations:

maybe you know the attribute name in advance, but don't know whether the
object has that particular attribute, then the 3 argument form of getattr
could be appropriate:

print getattr(x, 'attr', 'some default')

or if the attribute name isn't a valid Python identifier:

print getattr(x, 'class')