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The relationship could not be changed because one or more of the foreign-key properties is non-nulla
...iginal parent including the child item collection
var originalParent = _dbContext.ParentItems
.Where(p => p.ID == parent.ID)
.Include(p => p.ChildItems)
.SingleOrDefault();
// We assume that the parent is still in the DB and don't check for null
// Update s...
Is there a performance difference between i++ and ++i in C++?
... this->data += 1;
return *this;
}
Foo Foo::operator++(int ignored_dummy_value) // called for i++
{
Foo tmp(*this); // variable "tmp" cannot be optimized away by the compiler
++(*this);
return tmp;
}
Since the compiler isn't generating code, but just calling an operator++ ...
In PHP, can you instantiate an object and call a method on the same line?
...So, if you declared a class like this :
class Test {
public function __construct($param) {
$this->_var = $param;
}
public function myMethod() {
return $this->_var * 2;
}
protected $_var;
}
You can then declare a function that returns an instance of that ...
How to set -source 1.7 in Android Studio and Gradle
... }
compileOptions {
sourceCompatibility JavaVersion.VERSION_1_7
targetCompatibility JavaVersion.VERSION_1_7
}
}
Gradle 1.7+, Android gradle plugin 0.6.+ are required.
Note, that only try with resources require minSdkVersion 19. Other features works on previous platform...
Print list without brackets in a single row
...
@FredrickGauss if you add from __future__ import print_function it'll work in python 2 as well.
– Anthony Sottile
Aug 26 '17 at 22:07
1
...
Which commit has this blob?
...
Here it is as a shell script – short and sweet, but slow:
#!/bin/sh
obj_name="$1"
shift
git log "$@" --pretty=format:'%T %h %s' \
| while read tree commit subject ; do
if git ls-tree -r $tree | grep -q "$obj_name" ; then
echo $commit "$subject"
fi
done
And an optimised version ...
How to import a module given its name as string?
...hat's pretty much how you do it.
For newer versions, see importlib.import_module for Python 2 and and Python 3.
You can use exec if you want to as well.
Or using __import__ you can import a list of modules by doing this:
>>> moduleNames = ['sys', 'os', 're', 'unittest']
>>> m...
How to convert JSON data into a Python object
...E
With Python3, you can do it in one line, using SimpleNamespace and object_hook:
import json
from types import SimpleNamespace
data = '{"name": "John Smith", "hometown": {"name": "New York", "id": 123}}'
# Parse JSON into an object with attributes corresponding to dict keys.
x = json.loads(data, ...
How can I remove an element from a list, with lodash?
...in the comments, more idiomatic and lodashy way to do this would be to use _.remove, like this
_.remove(obj.subTopics, {
subTopicId: stToDelete
});
Apart from that, you can pass a predicate function whose result will be used to determine if the current element has to be removed or not.
_.rem...
How to write log base(2) in c/c++
...
#define M_LOG2E 1.44269504088896340736 // log2(e)
inline long double log2(const long double x){
return log(x) * M_LOG2E;
}
(multiplication may be faster than division)
...