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Django in / not in query
...e(); Tbl2.objects.filter(id__in=IDs') This did not work because IDs is actually a QuerySet object. When I deleted the rows it originated from, it no longer worked with other queries. The solution is Tbl2.objects.filter(id__in=list(IDs)) -- turn it into a list
– Dakusan
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How much is the overhead of smart pointers compared to normal pointers in C++?
..._ptr always has memory overhead for reference counter, though it is very small.
std::unique_ptr has time overhead only during constructor (if it has to copy the provided deleter and/or null-initialize the pointer) and during destructor (to destroy the owned object).
std::shared_ptr has time overhe...
Move capture in lambda
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Generalized lambda capture in C++14
In C++14 we will have the so called generalized lambda capture. This enables move capture. The following will be legal code in C++14:
using namespace std;
// a unique_ptr is move-only
auto u = make_unique<some_type>( some, parameters );
// move...
Why would introducing useless MOV instructions speed up a tight loop in x86_64 assembly?
... in the branch prediction table
moving the branch eliminated the alias and allowed the branch to be predicted correctly
Your Core2 doesn't keep a separate history record for each conditional jump. Instead it keeps a shared history of all conditional jumps. One disadvantage of global branch predic...
Can a C# lambda expression have more than one statement?
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(I'm assuming you're really talking about multiple statements rather than multiple lines.)
You can use multiple statements in a lambda expression using braces, but only the syntax which doesn't use braces can be converted into an expression tree:
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Are there conventions on how to name resources?
... and colors I use in those layouts. However, I do try generalizing. e.g if all buttons have a common textColor, I won't prefix the name with the layout. The resource name would be 'button_textColor'. If all textColors are using the same the resource it will be named 'textColor'. For Styles, this is ...
_DEBUG vs NDEBUG
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+1. NDEBUG in particular is allowed to be #undef'd and #define'd within a single TU (and reincluding <assert.h> changes the assert macro accordingly). Because this is different than expected/desired, it's common to use another macro to control a ...
Overloading Macro on Number of Arguments
I have two macros FOO2 and FOO3 :
8 Answers
8
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log messages appearing twice with Python Logging
I'm using Python logging, and for some reason, all of my messages are appearing twice.
8 Answers
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In Python, when should I use a function instead of a method?
...sulation which is so dear to OO design.
The encapsulation principal is really what this comes down to: as a designer you should hide everything about the implementation and class internals which it is not absolutely necessarily for any user or other developer to access. Because we deal with instan...