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How to convert Nonetype to int or string?
...t's your code, figure out how you're getting None when you expect a number and stop that from happening.
If it's someone else's code, find out the conditions under which it gives None and determine a sensible value to use for that, with the usual conditional code:
result = could_return_none(x)
if...
How do I test a private function or a class that has private methods, fields or inner classes?
..., z);
foo.privateField = value;
This way your code remains type-safe and readable. No design compromises, no overexposing methods and fields for the sake of tests.
If you have somewhat of a legacy Java application, and you're not allowed to change the visibility of your methods, the best wa...
Test iOS app on device without apple developer program or jailbreak
... has finally introduced a new feature in Xcode 7 that allows you to deploy and run any number of apps on any of your devices, simply by logging in with your Apple ID. You will no longer need a paid Program membership to deploy apps on your own device (and you certainly no longer have to jailbreak yo...
What is a “surrogate pair” in Java?
...mething about surrogate pairs . What is a surrogate pair in this context? And what are low and high surrogates?
7 An...
What is the Ruby (spaceship) operator?
...en return -1
if a = b then return 0
if a > b then return 1
if a and b are not comparable then return nil
It's useful for sorting an array.
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Django filter versus get for single object?
...lly implemented in Django, so there should be no "performance" difference (and the fact that you're thinking about it indicates you're violating one of the cardinal rules of programming, namely trying to optimize code before it's even been written and profiled -- until you have the code and can run ...
LINQ Single vs First
...ou mean the other.
Note: In my code, I will typically use FirstOrDefault() and SingleOrDefault() but that's a different question.
Take, for example, a table that stores Customers in different languages using a Composite Key ( ID, Lang ):
DBContext db = new DBContext();
Customer customer = db.Custome...
Add vertical whitespace using Twitter Bootstrap?
...ion in them. This is because those classes
are applied from min-width: 0 and up, and thus are not bound by a
media query. The remaining breakpoints, however, do include a
breakpoint abbreviation.
The classes are named using the format {property}{sides}-{size} for xs
and {property}{sides...
How to install Android SDK Build Tools on the command line?
I want to setup the Android dev environment from command line, and encounter the following issue:
19 Answers
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How to use git bisect?
...les saying that git bisect is awesome. However, I'm not a native speaker and I can't understand why it's awesome.
6 Answe...