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Aren't Python strings immutable? Then why does a + “ ” + b work?
...able, a, which points to the string, is mutable.
Consider:
a = "Foo"
# a now points to "Foo"
b = a
# b points to the same "Foo" that a points to
a = a + a
# a points to the new string "FooFoo", but b still points to the old "Foo"
print a
print b
# Outputs:
# FooFoo
# Foo
# Observe that b hasn't...
Python Git Module experiences? [closed]
What are people's experiences with any of the Git modules for Python? (I know of GitPython, PyGit, and Dulwich - feel free to mention others if you know of them.)
...
What is the copy-and-swap idiom?
...rray); // (3)
}
return *this;
}
And we say we're finished; this now manages an array, without leaks. However, it suffers from three problems, marked sequentially in the code as (n).
The first is the self-assignment test. This check serves two purposes: it's an easy way to prevent us fr...
How do I preview emails in Rails?
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Action Mailer now has a built in way of previewing emails in Rails 4.1. For example, check this out:
# located in test/mailers/previews/notifier_mailer_preview.rb
class NotifierPreview < ActionMailer::Preview
# Accessible from http:...
Surrogate vs. natural/business keys [closed]
...
Now, after reading a lot about surrogate keys and natural keys, I think using surrogate keys is better. But, on my database, natural keys (a NVARCHAR(20)) must be unique. I don't understand how I can get more speed if I need ...
How can I access my localhost from my Android device?
...hanks, this was for great help for me. The issue for me was that I didn't know that the local apache server could be addressed via the ip 10.0.2.2. ... I tries lots of other ip-adresses, like the one show by ipconfig etc. But again, thanks alot!
– Vidar Vestnes
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When should one use RxJava Observable and when simple Callback on Android?
...});
The RxJava variant is not much better than the Callback variant. For now, let's ignore the error handling.
Let's take a list of photos:
RxJava:
api.getUserPhotos(userId)
.subscribeOn(Schedulers.io())
.observeOn(AndroidSchedulers.mainThread())
.flatMap(new Func1<List<Photo>, Observab...
How does the paste image from clipboard functionality work in Gmail and Google Chrome 12+?
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Now that the first item in the list isn't always the file you pasted, I've updated it to loop through the items to find any pasted files.
– Nick Retallack
Sep 7 '15 at 20:28
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How to correctly iterate through getElementsByClassName
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for ... of allows you to iterate over NodeList now as in for (slide of slides) Distribute(slide). Browser support is patchy, but if you're transpiling then for ... of will be converted, but NodeList.forEach wouldn't.
– Mr5o1
Oct 22 ...
Why doesn't the height of a container element increase if it contains floated elements?
...ce blank -->
<div style="clear: both;"></div>
<!-- Now in order to prevent the next div from floating beside the top ones,
we use `clear: both;`. This is like a wall, so now none of the div's
will be floated after this point. The container height will now also...