Consider the following:
with open(path, mode) as f: return [line for line in f if condition]
Will the file be closed properly, or does using
return somehow bypass the context manager?
Yes, it acts like the
finally block after a
try block, i.e. it always executes (unless the python process terminates in an unusual way of course).
It is also mentioned in one of the examples of PEP-343 which is the specification for the
with locked(myLock): # Code here executes with myLock held. The lock is # guaranteed to be released when the block is left (even # if via return or by an uncaught exception).
Something worth mentioning is however, that you cannot easily catch exceptions thrown by the
open() call without putting the whole
with block inside a
try..except block which is usually not what one wants.
Cracking the Coding Interview PDF: 189 Programming Questions and Solutions, 6th Edition. I am not a recruiter. I am a software engineer. And as such, I know what it's like to be asked to create ing...
Target knows. Apple Computer knows, too. So do LinkedIn, Netflix, Facebook, Twitter, Expedia, national and local political campaigns, and dozens of other organizations that all generate enormous eco...
This book is not just about learning the code; even if you learn to program. If you want to program professionally, learning to code is not enough; For this reason, in addition to helping you program,...
As information protection continues to be a growing concern for businesses today, IT security certifications have become highly desirable, even as the number of certifications has grown. Now you can s...