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Null coalescing in powershell
...becomes one of the following (depending on preference):
$s = if ($myval -eq $null) { "new value" } else { $myval }
$s = if ($myval -ne $null) { $myval } else { "new value" }
or depending on what $myval might contain you could use:
$s = if ($myval) { $myval } else { "new value" }
and the second...
What's the status of multicore programming in Haskell?
... Simon Marlow -- more control over pure parallelism than strategies/par/pseq.
Cloud Haskell: Erlang-style message passing between distributed Haskell nodes.
Parallel Haskell: Embracing Diversity, a talk by SPJ.
Real time edge detection in parallel Haskell
Parallel Haskell Digest: news on parallel Ha...
How to change the commit author for one specific commit?
...dit
Exit the editor (for vim, this would be pressing Esc and then typing :wq).
Once the rebase started, it would first pause at C
You would git commit --amend --author="Author Name <email@address.com>"
Then git rebase --continue
It would pause again at D
Then you would git commit --amend --aut...
How to use Namespaces in Swift?
...
@Dai It seems that's why we should avoid Apple forums for Q&A... But core dev team members don't seem to care much on SO. What a tragedy.
– eonil
Oct 8 '18 at 13:27
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How do I byte-compile everything in my .emacs.d directory?
...
@nacho4d emacs -Q --batch -f batch-byte-compile *.el foo/*.el - it doesn't recurse like byte-recompile-directory does though.
– Brian Burns
Jan 10 '15 at 22:57
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Can not connect to local PostgreSQL
...ess the socket file. To confirm this I've done some tests on Ubuntu and psql to try to generate the same error (included below).
You need to check the permissions on the socket file and its directories /var and /var/pgsql_socket. Your Rails app (OSX user) must have execute (x) permissions on thes...
Escape double quotes in a string
Double quotes can be escaped like this:
6 Answers
6
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How to Convert all strings in List to lower case using LINQ?
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[TestMethod]
public void LinqStringTest()
{
List<string> myList = new List<string> { "aBc", "HELLO", "GoodBye" };
myList = (from s in myList select s.ToLower()).ToList();
Assert.AreEqual(myList[0], "abc");
Assert.AreEqual(myL...
How to select a node using XPath if sibling node has a specific value?
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Not sure why everybody is querying for siblings, you can also check for <bb/>-elements matching the predicate from <a/>'s predicate:
//a[bb/text() = "zz"]/cc/text()
...
push_back vs emplace_back
...CV10 is non conforming and redundant, because as you noted it is strictly equivalent to push_back(Type&& _Val).
But the real C++0x form of emplace_back is really useful: void emplace_back(Args&&...);
Instead of taking a value_type it takes a variadic list of arguments, so that mean...