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Is the C# static constructor thread safe?
...class.
private class InitializerTest
{
static private int _x;
static public string Status()
{
return "_x = " + _x;
}
static InitializerTest()
{
System.Diagnostics.Debug.WriteLine("InitializerTest() starting.");
...
How to make the 'cut' command treat same sequental delimiters as one?
...re. You could pass < text.txt directly to tr. en.wikipedia.org/wiki/Cat_%28Unix%29#Useless_use_of_cat
– arielf
Aug 9 '14 at 20:10
1
...
How to encrypt/decrypt data in php?
...er generator. The following example would be recommended (>= 5.3):
$key_size = 32; // 256 bits
$encryption_key = openssl_random_pseudo_bytes($key_size, $strong);
// $strong will be true if the key is crypto safe
This can be done once or multiple times (if you wish to create a chain of encrypti...
Easy pretty printing of floats in python?
...most exactly) this command you said you made up:
import numpy as np
np.set_printoptions(precision=2)
Or even better in your case if you still want to see all decimals of really precise numbers, but get rid of trailing zeros for example, use the formatting string %g:
np.set_printoptions(formatter...
In Python, using argparse, allow only positive integers
...still need to define an actual method that decides this for you:
def check_positive(value):
ivalue = int(value)
if ivalue <= 0:
raise argparse.ArgumentTypeError("%s is an invalid positive int value" % value)
return ivalue
parser = argparse.ArgumentParser(...)
parser.add_argu...
Objective-C declared @property attributes (nonatomic, copy, strong, weak)
...maticReferenceCounting.html#ownership.spelling.property
assign implies __unsafe_unretained ownership.
copy implies __strong ownership, as well as the usual behavior of copy
semantics on the setter.
retain implies __strong ownership.
strong implies __strong ownership.
unsafe...
Adding a new value to an existing ENUM Type
...he new type.
-- 1. rename the enum type you want to change
alter type some_enum_type rename to _some_enum_type;
-- 2. create new type
create type some_enum_type as enum ('old', 'values', 'and', 'new', 'ones');
-- 3. rename column(s) which uses our enum type
alter table some_table rename column some...
Twitter API returns error 215, Bad Authentication Data
...th https://dev.twitter.com and create application.
<?php
$token = 'YOUR_TOKEN';
$token_secret = 'YOUR_TOKEN_SECRET';
$consumer_key = 'CONSUMER_KEY';
$consumer_secret = 'CONSUMER_SECRET';
$host = 'api.twitter.com';
$method = 'GET';
$path = '/1.1/statuses/user_timeline.json'; // api call path
$q...
Why use apparently meaningless do-while and if-else statements in macros?
...mi-colon. Should the user view code not needing one...
doSomething(1) ;
DO_SOMETHING_ELSE(2) // <== Hey? What's this?
doSomethingElseAgain(3) ;
This means the user expects the compiler to produce an error if the semi-colon is absent.
But the real real good reason is that at some time, the ma...
In practice, what are the main uses for the new “yield from” syntax in Python 3.3?
... etc."""
for i in range(4):
yield '<< %s' % i
def reader_wrapper(g):
# Manually iterate over data produced by reader
for v in g:
yield v
wrap = reader_wrapper(reader())
for i in wrap:
print(i)
# Result
<< 0
<< 1
<< 2
<< 3
Instead of ...