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How to initialize an array in one step using Ruby?
...rray = [ '1', '2', '3' ]
You can also use a range:
array = ('1'..'3').to_a # parentheses are required
# or
array = *('1'..'3') # parentheses not required, but included for clarity
For arrays of whitespace-delimited strings, you can use Percent String syntax:
array = %w[ 1 2 3 ]
You can...
Is there a way to use SVG as content in a pseudo element :before or :after
...
<div class="author_">Lord Byron</div>
.author_ { font-family: 'Playfair Display', serif; font-size: 1.25em; font-weight: 700;letter-spacing: 0.25em; font-style: italic;
position:relative;
margin-top: -0.5em;
color: bla...
Two-way encryption: I need to store passwords that can be retrieved
...
/**
* Constructor!
*
* @param string $cipher The MCRYPT_* cypher to use for this instance
* @param int $mode The MCRYPT_MODE_* mode to use for this instance
* @param int $rounds The number of PBKDF2 rounds to do on the key
*/
public function __construct...
What is the most efficient way to deep clone an object in JavaScript?
...actical.
class StructuredCloner {
constructor() {
this.pendingClones_ = new Map();
this.nextKey_ = 0;
const channel = new MessageChannel();
this.inPort_ = channel.port1;
this.outPort_ = channel.port2;
this.outPort_.onmessage = ({data: {key, value}}) => {
const r...
python design patterns [closed]
...for their existence.
It's nothing more than
class Null(object):
def __init__(self, *args, **kwargs):
"Ignore parameters."
return None
def __call__(self, *args, **kwargs):
"Ignore method calls."
return self
def __getattr__(self, mname):
"Ignore...
What techniques can be used to speed up C++ compilation times?
...more than once in a single translation unit.
#pragma once
#ifndef filename_h
#define filename_h
// Header declarations / definitions
#endif
By using both the pragma and the ifndef, you get the portability of the plain macro solution, as well as the compilation speed optimization that some compi...
How to set environment variables in Python?
...
@darth_coder It's true for all processes on Unix-like operating systems. I don't know about the other operating system. Note that shell variables are not stored in the environment unless you export them.
– S...
Remove by _id in MongoDB console
...
Very close. This will work:
db.test_users.deleteOne( {"_id": ObjectId("4d512b45cc9374271b02ec4f")});
i.e. you don't need a new for the ObjectId.
Also, note that in some drivers/tools, remove() is now deprecated and deleteOne or deleteMany should be used ins...
How can I programmatically check whether a keyboard is present in iOS app?
...ade easier to use.
@interface KeyboardStateListener : NSObject {
BOOL _isVisible;
}
+ (KeyboardStateListener *)sharedInstance;
@property (nonatomic, readonly, getter=isVisible) BOOL visible;
@end
static KeyboardStateListener *sharedInstance;
@implementation KeyboardStateListener
+ (KeyboardS...
Facebook API - How do I get a Facebook user's profile image through the Facebook API (without requir
...rofile image from their Facebook URL (that is, http://facebook.com/users_unique_url ). How can I accomplish this? Is there a Faceboook API call that fetches a user's profile image URL without the user needing to Allow the application?
...