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“Notice: Undefined variable”, “Notice: Undefined index”, and “Notice: Undefined offset” using PHP
...e']) ? $_POST['value'] : '';
This has become much cleaner as of PHP 7.0, now you can use the null coalesce operator:
// Null coalesce operator - No need to explicitly initialize the variable.
$value = $_POST['value'] ?? '';
Set a custom error handler for E_NOTICE and redirect the messages away f...
How is “int* ptr = int()” value initialization not illegal?
...
@NeilG: This stays the same in C++11, though there is now also a nullptr, which you can use instead of 0 or NULL in new code.
– Jerry Coffin
Nov 9 '11 at 23:02
...
What does this mean: Failure [INSTALL_FAILED_CONTAINER_ERROR]?
...ecure folder, only root has access. I was able to run the app before, only now since a while, cannot run it and it gives the above error.
– Mathias Conradt
Apr 21 '11 at 13:27
1
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How do I run Asynchronous callbacks in Playground
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guard let data = data, error == nil else {
print(error ?? "Unknown error")
return
}
let contents = String(data: data, encoding: .utf8)
print(contents!)
}.resume()
PlaygroundPage.current.needsIndefiniteExecution = true
Or in Swift 2:
import UIKit
import XCPlaygro...
What is the difference between pip and conda?
I know pip is a package manager for python packages. However, I saw the installation on IPython's website use conda to install IPython.
...
How to access parent scope from within a custom directive *with own scope* in AngularJS?
... want to avoid something totally hacky or unmaintainable. For example, I know I could do it right now by taking the $scope from the preLink parameters and iterating over it's $sibling scopes to find the conceptual "parent".
...
How do I get the object if it exists, or None if it does not exist?
...u can do it this way:
go = Content.objects.filter(name="baby").first()
Now go variable could be either the object you want or None
Ref: https://docs.djangoproject.com/en/1.8/ref/models/querysets/#django.db.models.query.QuerySet.first
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Tips for debugging .htaccess rewrite rules
...nd 301 redirected to URL C. Even if URL C was the ultimate goal, you will know that this is bad for SEO and needs to be fixed.
You will be able to see cache headers that were set on the server side, replay requests, modify request headers to test ....
...
How do I capture SIGINT in Python?
...ython script that starts several processes and database connections. Every now and then I want to kill the script with a Ctrl + C signal, and I'd like to do some cleanup.
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What are good alternatives to SQL (the language)? [closed]
...n or local methods in SQL. I looked up ScalaQuery from your post (which is now called Slick) and rewrote the entire system and every 6 queries become 1, just because you could encapsulate and have local methods! If anyone is suffering from SQL horrors, look up Scala Slick or Quill and prepare for en...