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C++0x has no semaphores? How to synchronize threads?
...ex and a condition variable:
#include <mutex>
#include <condition_variable>
class semaphore
{
private:
std::mutex mutex_;
std::condition_variable condition_;
unsigned long count_ = 0; // Initialized as locked.
public:
void notify() {
std::lock_guard<decltype...
SQlite Getting nearest locations (with latitude and longitude)
...dPosition(center, mult * radius, 270);
strWhere = " WHERE "
+ COL_X + " > " + String.valueOf(p3.x) + " AND "
+ COL_X + " < " + String.valueOf(p1.x) + " AND "
+ COL_Y + " < " + String.valueOf(p2.y) + " AND "
+ COL_Y + " > " + String.valueOf(p4.y);
COL_X...
In-memory size of a Python structure
...g/measure-real-size-any-python-object/
The punchline:
import sys
def get_size(obj, seen=None):
"""Recursively finds size of objects"""
size = sys.getsizeof(obj)
if seen is None:
seen = set()
obj_id = id(obj)
if obj_id in seen:
return 0
# Important mark as s...
Django set field value after a form is initialized
...value after the form was submitted, you can use something like:
if form.is_valid():
form.cleaned_data['Email'] = GetEmailString()
Check the referenced docs above for more on using cleaned_data
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C# Lazy Loaded Automatic Properties
... 4.0 Lazy<T> type to create this pattern
private Lazy<string> _someVariable =new Lazy<string>(SomeClass.IOnlyWantToCallYouOnce);
public string SomeVariable => _someVariable.Value;
This code will lazily calculate the value of _someVariable the first time the Value expression i...
Timeout a command in bash without unnecessary delay
...t;Dmitry.Golovashkin@sas.com>
scriptName="${0##*/}"
declare -i DEFAULT_TIMEOUT=9
declare -i DEFAULT_INTERVAL=1
declare -i DEFAULT_DELAY=1
# Timeout.
declare -i timeout=DEFAULT_TIMEOUT
# Interval between checks if the process is still alive.
declare -i interval=DEFAULT_INTERVAL
# Delay between ...
Python argparse: Make at least one argument required
...
args = vars(parser.parse_args())
if not any(args.values()):
parser.error('No arguments provided.')
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How do I initialize a TypeScript object with a JSON object
... the json:
module Environment {
export class Member {
private __name__ = "Member";
id: number;
}
export class ExampleClass {
private __name__ = "ExampleClass";
mainId: number;
firstMember: Member;
secondMember: Member;
}
}
function ...
Flask-SQLAlchemy import/context issue
...
The flask_sqlalchemy module does not have to be initialized with the app right away - you can do this instead:
# apps.members.models
from flask_sqlalchemy import SQLAlchemy
db = SQLAlchemy()
class Member(db.Model):
# fields her...
How to automatically generate N “distinct” colors?
...uration [0, 100), lightness [0, 100)
for(i = 0; i < 360; i += 360 / num_colors) {
HSLColor c;
c.hue = i;
c.saturation = 90 + randf() * 10;
c.lightness = 50 + randf() * 10;
addColor(c);
}
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