object.enable() anti-pattern

[Dan Sommers]

On Wed, 08 May 2013 08:52:12 +0000, Steven D'Aprano wrote:

> This is an anti-pattern to avoid. The idea is that creating a resource 
> ought to be the same as "turning it on", or enabling it, or similar. For 
> example, we don't do this in Python:
> 
> f = file("some_file.txt")
> f.open()
> data = f.read()

So why don't we do this?

    data = read("some_file.txt")

> because reading the file can fail if you forget to call open first. 
> Instead, Python uses a factory function that creates the file object and 
> opens it:
> 
> f = open("some_file.txt")  # if this succeeds, f is ready to use
> data = f.read()

That's just the "enable" paradigm in a socially acceptable and
traditional wrapper.

Opening and closing the file is an implementation detail, often defeated
by caching (application level or OS level) anyway.

Dan