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Null coalescing in powershell
...ms -ne $null
[string]::Join(', ', ($instances | ForEach-Object -Process { $_.GetType() }))
# Result:
System.String, System.Int32, System.Int32, System.String, System.Object[],
System.Boolean, System.Boolean
-eq works similarly, which is useful for counting null entries:
($null, 'a', $null -eq $n...
*.h or *.hpp for your class definitions
... directly or indirectly.
It can included directly, being protected by the __cplusplus macro:
Which mean that, from a C++ viewpoint, the C-compatible code will be defined as extern "C".
From a C viewpoint, all the C code will be plainly visible, but the C++ code will be hidden (because it won't co...
New features in java 7
...OutputStream(dest))
{
// code
}
Underscores in numeric literals
int one_million = 1_000_000;
Strings in switch
String s = ...
switch(s) {
case "quux":
processQuux(s);
// fall-through
case "foo":
case "bar":
processFooOrBar(s);
break;
case "baz":
processBaz(s);
...
Delete files older than 10 days using shell script in Unix [duplicate]
...
find is the common tool for this kind of task :
find ./my_dir -mtime +10 -type f -delete
EXPLANATIONS
./my_dir your directory (replace with your own)
-mtime +10 older than 10 days
-type f only files
-delete no surprise. Remove it to test your find filter before executing the wh...
SQLAlchemy - Getting a list of tables
...the baseclass,
>>> Base = sqlalchemy.ext.declarative.declarative_base()
>>> Base.metadata
MetaData(None)
If you are trying to figure out what tables are present in your database, even among the ones you haven't even told SQLAlchemy about yet, then you can use table reflection. ...
Toggle button using two image on different state
...
<ToggleButton
android:id="@+id/toggle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@drawable/check" <!--check.xml-->
android:layout_margin="10dp"
android:textOn=""
android:textOff="...
ActiveModel::ForbiddenAttributesError when creating new user
...ntroller < ApplicationController
def create
@user = User.new(user_params)
# ...
end
private
def user_params
params.require(:user).permit(:username, :email, :password, :salt, :encrypted_password)
end
end
...
Circular (or cyclic) imports in Python
...be partly empty.
Finally, the executing script runs in a module named __main__, importing
the script under its own name will create a new module unrelated to
__main__.
Take that lot together and you shouldn't get any surprises when importing
modules.
...
How to disable Django's CSRF validation?
...
If you just need some views not to use CSRF, you can use @csrf_exempt:
from django.views.decorators.csrf import csrf_exempt
@csrf_exempt
def my_view(request):
return HttpResponse('Hello world')
You can find more examples and other scenarios in the Django documentation:
https:/...
Unexpected Caching of AJAX results in IE8
... not as simple to solve.
The trick is to use Sys.Net.WebRequestManager.add_invokingRequest method in the event handler change the request url:
networkRequestEventArgs._webRequest._url = networkRequestEventArgs._webRequest._url + '&nocache=' + new Date().getMilliseconds();
I've blogged about...