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What does an exclamation mark mean in the Swift language?
...d optionals should not be used when there is a possibility of a variable becoming nil at a later point. Always use a normal optional type if you need to check for a nil value during the lifetime of a variable.
Update 2:
The article "Interesting Swift Features" by Mike Ash gives some motivation fo...
How do you detect Credit card type based on number?
...abase is not publicly available, however, there are unofficial lists, both commercial and free, including on Wikipedia.
Anyway, to detect the type from the number, you can use a regular expression like the ones below: Credit for original expressions
Visa: ^4[0-9]{6,}$ Visa card numbers start with ...
Build an ASCII chart of the most commonly used words in a given text [closed]
Build an ASCII chart of the most commonly used words in a given text.
59 Answers
59
...
What's the best way to get the last element of an array without deleting it?
...s , count , end , reset)
The test inputs (<<input code>>s) to combine with:
null = $array = null;
empty = $array = [];
last_null = $array = ["a","b","c",null];
auto_idx = $array = ["a","b","c","d"];
shuffle = $array = []; $array[1] = "a"; $array[2] = "b"; $array[0] = "c";
100 = $arra...
Interfaces — What's the point?
...nd probably just shrugs and says »Meh.« if it doesn't. Not so in C#. The compiler is responsible for making the correct calls and if it just has some random object the compiler doesn't know yet whether the instance during runtime will have that method. From the compiler's point of view it's invali...
What does 'COLLATE SQL_Latin1_General_CP1_CI_AS' do?
...
It sets how the database server sorts (compares pieces of text). in this case:
SQL_Latin1_General_CP1_CI_AS
breaks up into interesting parts:
latin1 makes the server treat strings using charset latin 1, basically ascii
CP1 stands for Code Page 1252
CI case in...
Saving an Object (Data persistence)
...e's an elementary application of it to your example:
import pickle
class Company(object):
def __init__(self, name, value):
self.name = name
self.value = value
with open('company_data.pkl', 'wb') as output:
company1 = Company('banana', 40)
pickle.dump(company1, output, ...
Resumable downloads when using PHP to send the file?
...tic, apparently the client can request
// multiple ranges, which can become pretty complex, so ignore it for now
preg_match('/bytes=(\d+)-(\d+)?/', $_SERVER['HTTP_RANGE'], $matches);
$offset = intval($matches[1]);
$length = intval($matches[2]) - $offset;
} else {
$partialContent...
What is the difference between a strongly typed language and a statically typed language?
...nguage?
A statically typed language has a type system that is checked at compile time by the implementation (a compiler or interpreter). The type check rejects some programs, and programs that pass the check usually come with some guarantees; for example, the compiler guarantees not to use intege...
What is the list of supported languages/locales on Android?
...bic (Israel)]
ar_IQ [Arabic (Iraq)]
ar_JO [Arabic (Jordan)]
ar_KM [Arabic (Comoros)]
ar_KW [Arabic (Kuwait)]
ar_LB [Arabic (Lebanon)]
ar_LY [Arabic (Libya)]
ar_MA [Arabic (Morocco)]
ar_MR [Arabic (Mauritania)]
ar_OM [Arabic (Oman)]
ar_PS [Arabic (Palestine)]
ar_QA [Arabic (Qatar)]
ar_SA [Arabic (Sau...