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Strangest language feature
What is, in your opinion, the most surprising, weird, strange or really "WTF" language feature you have encountered?
320 An...
What is global::?
...ss System
{
}
}
If you were to use System where it would be locally scoped in the foo class, you could use:
global::System.Console.WriteLine("foobar");
to access the global namespace.
Example
using System;
class Foo
{
public void baz()
{
Console.WriteLine("Foo 1");
...
Java associative-array
...'t PHP more permissive with $arr[0]['name'] (I don't know this language at all)?
– Tomasz Nurkiewicz
Feb 25 '11 at 21:49
9
...
What is the difference between a symbolic link and a hard link?
... (Or is it multiple inodes? Not sure.)
A file in the file system is basically a link to an inode.
A hard link, then, just creates another file with a link to the same underlying inode.
When you delete a file, it removes one link to the underlying inode. The inode is only deleted (or deletable/ove...
Case insensitive searching in Oracle
...
Since 10gR2, Oracle allows to fine-tune the behaviour of string comparisons by setting the NLS_COMP and NLS_SORT session parameters:
SQL> SET HEADING OFF
SQL> SELECT *
2 FROM NLS_SESSION_PARAMETERS
3 WHERE PARAMETER IN ('NLS_COMP', ...
SQL keys, MUL vs PRI vs UNI
... non-unique index, then why does MUL show against only that column and not all other columns as well.?
– Vikas Goel
Jun 15 '19 at 23:23
2
...
How to test that no exception is thrown?
... test your functionality: if an exception is thrown the test will automatically fail. If no exception is thrown, your tests will all turn up green.
I have noticed this question garners interest from time to time so I'll expand a little.
Background to unit testing
When you're unit testing it's imp...
Get elements by attribute when querySelectorAll is not available without using libraries?
... and returns only those elements with a "data-foo" attribute:
function getAllElementsWithAttribute(attribute)
{
var matchingElements = [];
var allElements = document.getElementsByTagName('*');
for (var i = 0, n = allElements.length; i < n; i++)
{
if (allElements[i].getAttribute(attri...
How can I pretty-print JSON in a shell script?
...ou can use
curl http://my_url/ | python -m json.tool
For convenience in all of these cases you can make an alias:
alias prettyjson='python -m json.tool'
For even more convenience with a bit more typing to get it ready:
prettyjson_s() {
echo "$1" | python -m json.tool
}
prettyjson_f() {...
Connect Java to a MySQL database
...
Here's a step by step explanation how to install MySQL and JDBC and how to use it:
Download and install the MySQL server. Just do it the usual way. Remember the port number whenever you've changed it. It's by default 3306.
Download the JDBC driver and put in classpath...