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Why no generics in Go?
... does Go not have generic types?
Generics may well be added at some point. We don't feel an urgency for them, although we understand some programmers do.
Generics are convenient but they come at a cost in complexity in the type system and run-time. We haven't yet found a design that gives ...
Are Java static calls more or less expensive than non-static calls?
... benchmarking code has an additional constant overhead of incrementing one integer variable, checking a boolean variable, and looping if not true.
I suppose the results will vary from CPU to CPU, and from JVM to JVM, so give it a try and see what you get:
import java.io.*;
class StaticVsInstanceB...
Why is null an object and what's the difference between null and undefined?
... null
true
A common way of checking whether a variable has a value is to convert it to boolean and see whether it is true. That conversion is performed by the if statement and the boolean operator ! (“not”).
function foo(param) {
if (param) {
// ...
}
}
function foo(param) {
...
String.replaceAll single backslashes with double backslashes
I'm trying to convert the String \something\ into the String \\something\\ using replaceAll , but I keep getting all kinds of errors. I thought this was the solution:
...
Using Enums while parsing JSON with GSON
...on(new FileReader("input.json"), TruncateElement.class);
System.out.println(element.lower);
System.out.println(element.upper);
System.out.println(element.delimiter);
System.out.println(element.scope.get(0));
}
}
class AttributeScopeDeserializer implements JsonDeserializer<Attr...
Hashing a dictionary?
...thon 3.3 returns different results between sessions). make_hashable() will convert the object into nested tuples and make_hash_sha256() will also convert the repr() to a base64 encoded SHA256 hash.
import hashlib
import base64
def make_hash_sha256(o):
hasher = hashlib.sha256()
hasher.updat...
MySQL error: key specification without a key length
... TEXT(88) simply won’t work.
The error will also pop up when you try to convert a table column from non-TEXT and non-BLOB type such as VARCHAR and ENUM into TEXT or BLOB type, with the column already been defined as unique constraints or index. The Alter Table SQL command will fail.
The solution...
Can inner classes access private variables?
...rivate:
static const char* const MYCONST;
Inner i;
int var;
};
const char* const Outer::MYCONST = "myconst";
int main()
{
Outer o1;
Outer o2(o1);
o1.func();
o2.func();
}
...
Favicon dimensions? [duplicate]
...upport possible. You upload an image and this site gives you the code, the converted images and a browserconfig file.
We could simply upload a favicon manually to our website of 16x16 and it will probably show up in almost any browser.
But when you will mark it as one of your favorites on your s...
Are arrays passed by value or passed by reference in Java? [duplicate]
...reference will affect the original array..
But changing the reference to point to a new array will not change the existing reference in original method..
See this post..
Is Java "pass-by-reference" or "pass-by-value"?
See this working example: -
public static void changeContent(int[] arr) {
...