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Declaring and initializing variables within Java switches
...in other cases - it leads to highly confusing code, as you've seen. When I introduce local variables in switch statements (which I try to do rarely - cases should be very short, ideally) I usually prefer to introduce a new scope:
case 1: {
int value = 1;
...
break;
}
case 2: {
int v...
How does delete[] know it's an array?
...er doesn't know it's an array, it's trusting the programmer. Deleting a pointer to a single int with delete [] would result in undefined behavior. Your second main() example is unsafe, even if it doesn't immediately crash.
The compiler does have to keep track of how many objects need to be delete...
Node.js throws “btoa is not defined” error
...mmatic interface, it only provides command line utilities.
If you need to convert to Base64 you could do so using Buffer:
console.log(Buffer.from('Hello World!').toString('base64'));
Reverse (assuming the content you're decoding is a utf8 string):
console.log(Buffer.from(b64Encoded, 'base64').t...
What is the yield keyword used for in C#?
...e function returns an object that implements the IEnumerable<object> interface. If a calling function starts foreaching over this object, the function is called again until it "yields". This is syntactic sugar introduced in C# 2.0. In earlier versions you had to create your own IEnumerable and...
Why are preprocessor macros evil and what are the alternatives?
... != 0) res = x/y;
and then
if (something) safe_divide(b, a, x);
else printf("Something is not set...");
It actually becomes completely the wrong thing....
Replacement: real functions.
3) Macros have no namespace
If we have a macro:
#define begin() x = 0
and we have some code in C++ tha...
Javascript object Vs JSON
...worth noting that a key in JSON must be enclosed in double quotes.
If I convert the above object to JSON using var jSonString = JSON.stringify(testObject);, what is the difference between the 2 (JS obj and JSON)?
JSON is a data interchange format. It's a standard which describes how ordered lis...
Python: changing value in a tuple
...basically two ways of replacing a tuple's element at a given index. Either convert the tuple to a list, replace the element and convert back, or construct a new tuple by concatenation.
In [1]: def replace_at_index1(tup, ix, val):
...: lst = list(tup)
...: lst[ix] = val
...: ret...
Creating an index on a table variable
... that first.
SQL Server 2014
In addition to the methods of adding constraint based indexes discussed below SQL Server 2014 also allows non unique indexes to be specified directly with inline syntax on table variable declarations.
Example syntax for that is below.
/*SQL Server 2014+ compatible i...
Get the length of a String
...0;, Snail &#128012;, Penguin &#128039;, Dromedary &#128042;"
println("unusualMenagerie has \(count(unusualMenagerie)) characters")
// prints "unusualMenagerie has 40 characters"
right from the Apple Swift Guide
(note, for versions of Swift earlier than 1.2, this would be countElements...
Linq list of lists to single list
...
Here is a sample code for you:
List<int> listA = new List<int> { 1, 2, 3, 4, 5, 6 };
List<int> listB = new List<int> { 11, 12, 13, 14, 15, 16 };
List<List<int>> listOfLists = new List<List<int>> { listA, listB };
...