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Draw line in UIView
... to do it. For example, I want to draw a black horizontal line at y-coord=200.
8 Answers
...
Java to Clojure rewrite
I have just been asked by my company to rewrite a largish (50,000 single lines of code) Java application (a web app using JSP and servlets) in Clojure. Has anyone else got tips as to what I should watch out for?
...
What is the advantage of using forwarding references in range-based for loops?
...der:
#include <vector>
int main()
{
std::vector<bool> v(10);
for (auto& e : v)
e = true;
}
This doesn't compile because rvalue vector<bool>::reference returned from the iterator won't bind to a non-const lvalue reference. But this will work:
#include <v...
Where can I find documentation on formatting a date in JavaScript?
...
1069
I love 10 ways to format time and date using JavaScript and Working with Dates.
Basically, yo...
Convert between UIImage and Base64 string
...ta format
let imageData:NSData = NSData.init(contentsOfURL: url)!
Swift 2.0 > Encoding
let strBase64:String = imageData.base64EncodedStringWithOptions(.Encoding64CharacterLineLength)
Swift 2.0 > Decoding
let dataDecoded:NSData = NSData(base64EncodedString: strBase64, options: NSDataBase64Dec...
How to configure slf4j-simple
...
Evgeniy DorofeevEvgeniy Dorofeev
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What’s the difference between “Array()” and “[]” while declaring a JavaScript array?
...hese are the same
b = new Array(), // a and b are arrays with length 0
c = ['foo', 'bar'], // these are the same
d = new Array('foo', 'bar'), // c and d are arrays with 2 strings
// these are different:
e = [3] // e.length == 1, e[0] == 3
f = new Ar...
JavaScript checking for null vs. undefined and difference between == and ===
...
+50
How do I check a variable if it's null or undefined...
Is the variable null:
if (a === null)
// or
if (a == null) // but see not...
Loop backwards using indices in Python?
I am trying to loop from 100 to 0. How do I do this in Python?
15 Answers
15
...
CHECK constraint in MySQL is not working
...
MySQL 8.0.16 is the first version that supports CHECK constraints.
Read https://dev.mysql.com/doc/refman/8.0/en/create-table-check-constraints.html
If you use MySQL 8.0.15 or earlier, the MySQL Reference Manual says:
The CHECK...