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Regular expression to match balanced parentheses
...o at regex101; The pattern is pasted at (?R) which represents (?0).
Perl, PHP, Notepad++, R: perl=TRUE, Python: Regex package with (?V1) for Perl behaviour.
Ruby using subexpression calls.
With Ruby 2.0 \g<0> can be used to call full pattern.
\((?>[^)(]+|\g<0>)*\)
Demo at Rubu...
How can I copy the output of a command directly into my clipboard?
...e Jan 24 23:00:00 EST 2017
Paste
# clipboard retained from the previous block
$ cb
Tue Jan 24 23:00:00 EST 2017
$ cb | cat
Tue Jan 24 23:00:00 EST 2017
$ cb > foo
$ cat foo
Tue Jan 24 23:00:00 EST 2017
Chaining
$ date | cb | tee updates.log
Tue Jan 24 23:11:11 EST 2017
$ cat updates.log
Tue...
Postgres unique constraint vs index
...
There is a difference in locking.
Adding an index does not block read access to the table.
Adding a constraint does put a table lock (so all selects are blocked) since it is added via ALTER TABLE.
share
...
Using a dispatch_once singleton model in Swift
...e behaviour is not undefined, it is just broken in a well-defined way: the block will always execute.
– Michael
Jun 10 '14 at 10:54
...
How can I convert an image into a Base64 string?
...m i can put that String (encondedImage) into a remote database column with PHP+JSON ???? wich type haves to be the column of the database? VARCHAR?
– NullPointerException
Jan 28 '11 at 19:46
...
Best way to work with transactions in MS SQL Server Management Studio
...ou want to incorporate error handling you can do so by using a TRY...CATCH BLOCK. Should an error occur you can then rollback the tranasction within the catch block.
For example:
USE AdventureWorks;
GO
BEGIN TRANSACTION;
BEGIN TRY
-- Generate a constraint violation error.
DELETE FROM Prod...
Comparing Timer with DispatcherTimer
...ould stick to Dispatcher Timer, and then do your WORK (which is what could block your UI) in another thread, using something like a BackgroundWorker. The timers really should never block your UI, unless you're doing "too much" work in their event handler.
– Reed Copsey
...
How to affect other elements when one element is hovered
... hovers over #light somewhere inside #explainBox
set display to inline-block for #light directly inside of #definitions.*/
#explainBox #light:hover~#definitions>#light {
display: inline-block;
}
.def {
display: none;
}
#definitions {
background-color: black;
position: fixed;
/*po...
Prevent users from submitting a form by hitting Enter
...t).is('textarea') to the condition, or else newlines inside a textarea are blocked (in IE at least).
– Flash
Aug 8 '12 at 6:47
...
Can media queries resize based on a div element instead of the screen?
..., each made up of three orange divs labelled a, b and c.
The second two's blocks display vertically, because they are limited on horizontal room, while the top components 3 blocks are laid out horizontally.
It uses the flex-basis CSS property and CSS Variables to create this effect.
.panel{
d...