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Chaining multiple filter() in Django, is this a bug?
...style of filtering are equivalent in most cases, but when query on objects base on ForeignKey or ManyToManyField, they are slightly different.
Examples from the documentation.
model
Blog to Entry is a one-to-many relation.
from django.db import models
class Blog(models.Model):
...
class Entry(...
What is the difference between min SDK version/target SDK version vs. compile SDK version?
...nnel on Android 7.1 and lower).
Starting in Android 9 (API level 28), Web-based data directories separated by process. If targetSdkVersion is 28+ and you create several WebView in different processes you will get java.lang.RuntimeException
compileSdkVersion - actually it is SDK Platform version a...
Can JSON start with “[”?
...t a data format that is interchangeable with programming languages also be based on these structures.
In JSON, they take on these forms:
OBJECT:
An object is an unordered set of name/value pairs. An object begins with { (left brace) and ends with } (right brace). Each name is followed by :...
Good example of livelock?
...understand what livelock is, but I was wondering if anyone had a good code-based example of it? And by code-based, I do not mean "two people trying to get past each other in a corridor". If I read that again, I'll lose my lunch.
...
What does template mean?
...
You templatize your class based on an 'unsigned int'.
Example:
template <unsigned int N>
class MyArray
{
public:
private:
double data[N]; // Use N as the size of the array
};
int main()
{
MyArray<2> a1;
My...
ASP.NET Web Site or ASP.NET Web Application?
... You can still compile your entire site into a dll with the file based Web Site.
– dtc
Dec 31 '08 at 22:48
31
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What happens if you static_cast invalid value to enum class?
...ted underlying type.
Note: The underlying type of a scoped enum w/o enum-base is int. For unscoped enums the underlying type is implementation-defined, but shall not be larger than int if int can contain the values of all enumerators.
For an unscoped enumeration, this leads us to /1
A prvalue...
I want to get the type of a variable at runtime
... is the same class as b
A ClassTag is limited in that it only covers the base class, but not its type parameters. That is, the ClassTag for List[Int] and List[String] is the same, List. If you need type parameters, then you must use a TypeTag instead. A TypeTag however, cannot be obtained from a v...
Can I combine :nth-child() or :nth-of-type() with an arbitrary selector?
...d() and :nth-of-type() work. Unfortunately, there is currently no selector-based solution as yet because Selectors does not provide a way to match the nth child that matches an arbitrary selector based on a pattern such as odd-numbered, even-numbered or any an+b where a != 1 and b != 0. This extends...
Is mathematics necessary for programming? [closed]
... process of programming and mathematics are very similar. You begin with a base of known things (axioms, previously proven theories) and try to get to someplace new. You cannot skip steps. If you do skip steps, then you are required to fill in the blanks. It's a critical thought process that makes t...