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Why is there no tuple comprehension in Python?
...an the comprehension syntax is not needed? Perhaps not, but it is awfully handy. For the rare cases you need a tuple instead, the generator expression will do, is clear, and doesn't require the invention of another brace or bracket.
– Martijn Pieters♦
Jun 5 '...
Check if a file exists with wildcard in shell script [duplicate]
... completely silent.
EDIT: Since this answer has got a bit of attention (and very useful critic remarks as comments), here is an optimization that also relies on glob expansion, but avoids the use of ls:
for f in /path/to/your/files*; do
## Check if the glob gets expanded to existing files.
...
Using a dispatch_once singleton model in Swift
...tl;dr: Use the class constant approach if you are using Swift 1.2 or above and the nested struct approach if you need to support earlier versions.
From my experience with Swift there are three approaches to implement the Singleton pattern that support lazy initialization and thread safety.
Class c...
Laravel migration: unique key is too long, even if specified
...l', 250);
Which is the default, actually:
$table->string('email');
And you should be good.
For Laravel 5.4 you can find a solution in this Laravel 5.4: Specified key was too long error, Laravel News post:
As outlined in the Migrations guide to fix this all you have to do is edit your AppSe...
mongo group query how to keep fields
...
@Juliomac, I believe if your desired output is $max/$min and keeping fields that are not in the $group _id, you can $sort before with the desired field then group and use $first or $last operators on any field. When accumulating, the idea to include other fields (which are accumula...
How to set auto increment primary key in PostgreSQL?
I have a table in PostgreSQL with 22 columns, and I want to add an auto increment primary key.
7 Answers
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Incrementing in C++ - When to use x++ or ++x?
I'm currently learning C++ and I've learned about the incrementation a while ago.
I know that you can use "++x" to make the incrementation before and "x++" to do it after.
...
multi-step registration process issues in asp.net mvc (split viewmodels, single model)
... [Required]
public string SomeOtherProperty { get; set; }
...
}
and so on. All those view models could be backed by a main wizard view model:
public class WizardViewModel
{
public Step1ViewModel Step1 { get; set; }
public Step2ViewModel Step2 { get; set; }
...
}
then you co...
Prevent onmouseout when hovering child element of the parent absolute div WITHOUT jQuery
...tion onMouseOut(event) {
//this is the original element the event handler was assigned to
var e = event.toElement || event.relatedTarget;
if (e.parentNode == this || e == this) {
return;
}
alert('MouseOut');
// handle mouse event here!
}
document...
What is Angular.noop used for?
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@abyrne85 It is more aesthetically pleasing and a good practice to use angular.noop as you always reuse the same empty function (instead of declaring a new anonymous function everytime). Performance-wise it makes no difference as the code for angular.noop is just an em...