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Is False == 0 and True == 1 an implementation detail or is it guaranteed by the language?
...results, whatever the version of Python (both existing and, likely, future ones)?
6 Answers
...
What is the use of ObservableCollection in .net?
...enever I remove something from the list: she get's a notification on her phone (i.e. sms / email etc)!
The observable collection works just the same way. If you add or remove something to or from it: someone is notified. And when they are notified, well then they call you and you'll get a ear-full. ...
How can I initialize a String array with length 0 in Java?
...said,
new String[0]
will indeed create an empty array. However, there's one nice thing about arrays - their size can't change, so you can always use the same empty array reference. So in your code, you can use:
private static final String[] EMPTY_ARRAY = new String[0];
and then just return EMP...
Focus Input Box On Load
...h because Opera is inconsistent about
// whether a carriage return is one character or two.
var len = this.value.length * 2;
this.setSelectionRange(len, len);
} else {
// This might work for browsers without setSelectionRange support.
this.value = this.value;
}
if (this.n...
MySQL vs MongoDB 1000 reads
...ormance.
In MongoDB, to retrieve the whole entity, you have to perform:
One index lookup on the collection (assuming the entity is fetched by id)
Retrieve the contents of one database page (the actual binary json document)
So a b-tree lookup, and a binary page read. Log(n) + 1 IOs. If the index...
How do I invoke a Java method when given the method name as a string?
...
Plus one for showing some potential exceptions. If I had written this, it would be ... catch(Exception e){ ...
– mikbanUtah
Dec 11 '14 at 6:32
...
Use of .apply() with 'new' operator. Is this possible?
...mething, [null, a, b, c]));
This and the eval-based solution are the only ones that always work, even with special constructors like Date:
var date = newCall(Date, 2012, 1);
console.log(date instanceof Date); // true
edit
A bit of explanation:
We need to run new on a function that takes a limited...
Why does datetime.datetime.utcnow() not contain timezone information?
Why does this datetime not have any timezone info given that it is explicitly a UTC datetime ?
9 Answers
...
Font size in CSS - % or em?
...mobile devices have a device pixel ratio larger than 1. For example the iPhone 4 has a physical screen width of 640px, but appears as 320 "CSS" pixels (DPR=2). So the website does not appear smaller!
– Benjamin
Feb 28 '18 at 13:30
...
Add UIPickerView & a Button in Action sheet - How?
...ining a simple tableview.
There are many ways to accomplish this. Here's one way that I just implemented in a current project. It's nice because I can reuse it between 5 or 6 different screens where I all users to select from a list of options.
Create a new UITableViewController subclass, Simple...