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Inheritance and Overriding __init__ in python
...
The book is a bit dated with respect to subclass-superclass calling. It's also a little dated with respect to subclassing built-in classes.
It looks like this nowadays:
class FileInfo(dict):
"""store file metadata"""
def __init__(self, filename=None):
super(FileInfo,...
How to get the parents of a Python class?
...
If you want all the ancestors rather than just the immediate ones, use inspect.getmro:
import inspect
print inspect.getmro(cls)
Usefully, this gives you all ancestor classes in the "method resolution order" -- i.e. the order in which ...
How to create a HTTP server in Android? [closed]
...ening,use NetworkInterface.getNetworkInterfaces(), this question may tell extra tricks.
Finally, here there is possibly the complete minimal Android server that is very short, simple and may be easier to understand than finished end user applications, recommended in other answers.
...
C# Entity-Framework: How can I combine a .Find and .Include on a Model Object?
...=> p.Blog).Load();
// Load the blog related to a given post using a string
context.Entry(post).Reference("Blog").Load();
var blog = context.Blogs.Find(1);
// Load the posts related to a given blog
context.Entry(blog).Collection(p => p.Posts).Load();
// Load the posts rel...
Does the 'mutable' keyword have any purpose other than allowing the variable to be modified by a con
...l state such as a cache. For example:
class HashTable
{
...
public:
string lookup(string key) const
{
if(key == lastKey)
return lastValue;
string value = lookupInternal(key);
lastKey = key;
lastValue = value;
return value;
}
priv...
Java equivalent of unsigned long long?
...345");
To print it, you can not simply print l1, but you have to first:
String l1Str = Long.toUnsignedString(l1)
Then
System.out.println(l1Str);
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Check image width and height before upload with Javascript
...te the JavaScript Image object.
var image = new Image();
//Set the Base64 string return from FileReader as source.
image.src = e.target.result;
//Validate the File Height and Width.
image.onload = function () {
var height = this.height;
var width = this.width;
if (height > 100 || width &g...
Is a Java hashmap search really O(1)?
... 2 = (n / capacity)2
This is much lower. Since the cost of handling one extra collision is irrelevant to Big O performance, we've found a way to improve performance without actually changing the algorithm! We can generalzie this to
pcollision x k = (n / capacity)k
And now we can disregard...
Postgres and Indexes on Foreign Keys and Primary Keys
...le, you will have an index on the PK and probably don't need to create any extra indexes.
While it's usually a good idea to create an index on (or including) your referencing-side foreign key columns, it isn't required. Each index you add slows DML operations down slightly, so you pay a performance...
Use of undeclared identifier 'kUTTypeMovie'
...ker.sourceType = .camera
imagePicker.mediaTypes = [kUTTypeMovie as String]
imagePicker.videoMaximumDuration = 10 // or whatever you want
imagePicker.videoQuality = .typeMedium
imagePicker.allowsEditing = false
present(imagePicker, animated: true, completion: n...
