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Dictionaries and default values
...collections import defaultdict
a = defaultdict(lambda: "default", key="some_value")
a["blabla"] => "default"
a["key"] => "some_value"
You can pass any ordinary function instead of lambda:
from collections import defaultdict
def a():
return 4
b = defaultdict(a, key="some_value")
b['absent...
Where can I find my .emacs file for Emacs running on Windows?
I tried looking for the .emacs file for my Windows installation for Emacs, but I could not find it. Does it have the same filename under Windows as in Unix?
...
How do I space out the child elements of a StackPanel?
...fine the type (e.g. TextBox)? If I try this using FrameworkElement so that all children are spaced, it has no effect.
– Jack Ukleja
Jan 28 '14 at 18:48
5
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Is it possible to implement dynamic getters/setters in JavaScript?
...Here's a simple example that turns any property values that are strings to all caps on retrieval:
"use strict";
if (typeof Proxy == "undefined") {
throw new Error("This browser doesn't support Proxy");
}
let original = {
"foo": "bar"
};
let proxy = new Proxy(original, {
get(...
List of tables, db schema, dump etc using the Python sqlite3 API
...te("SELECT name FROM sqlite_master WHERE type='table';")
print(cursor.fetchall())
Watch out for my other answer. There is a much faster way using pandas.
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What is the purpose of “return await” in C#?
...n async method behave differently: when combined with using (or, more generally, any return await in a try block).
Consider these two versions of a method:
Task<SomeResult> DoSomethingAsync()
{
using (var foo = new Foo())
{
return foo.DoAnotherThingAsync();
}
}
async Tas...
How do Python functions handle the types of the parameters that you pass in?
...object has a type, every object knows its type, it's impossible to accidentally or deliberately use an object of a type "as if" it was an object of a different type, and all elementary operations on the object are delegated to its type.
This has nothing to do with names. A name in Python doesn't "...
Update relationships when saving changes of EF4 POCO objects
...ost to context. After attaching object to context the state of the object, all related objects and all relations is set to Unchanged.
Use context.ObjectStateManager.ChangeObjectState to set your BlogPost to Modified
Iterate through Tag collection
Use context.ObjectStateManager.ChangeRelationshipStat...
Easy idiomatic way to define Ordering for a simple case class
...[...] to Ordered[TupleN[...]] provided an implicit Ordering[TN] exists for all elements T1, ..., TN of the tuple, which should always be the case because it makes no sense to sort on a data type with no Ordering.
The implicit ordering for Tuples is your go-to for any sorting scenario involving a co...
What's the difference between eval, exec, and compile?
...
The short answer, or TL;DR
Basically, eval is used to evaluate a single dynamically generated Python expression, and exec is used to execute dynamically generated Python code only for its side effects.
eval and exec have these two differences:
eval accep...