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Is False == 0 and True == 1 an implementation detail or is it guaranteed by the language?
.....] Boolean values behave like the values 0 and 1, respectively, in almost all contexts, the exception being that when converted to a string, the strings "False" or "True" are returned, respectively.
There is also, for Python 2:
In numeric contexts (for example when used as the argument to an ...
What is the documents directory (NSDocumentDirectory)?
...ath = paths.firstObject;
return basePath;
}
This Documents directory allows you to store files and subdirectories your app creates or may need.
To access files in the Library directory of your apps sandbox use (in place of paths above):
[NSSearchPathForDirectoriesInDomains(NSLibraryDirectory...
How do I profile memory usage in Python?
...
This one has been answered already here: Python memory profiler
Basically you do something like that (cited from Guppy-PE):
>>> from guppy import hpy; h=hpy()
>>> h.heap()
Partition of a set of 48477 objects. Total size = 3265516 bytes.
Index Count % Size % Cumulat...
How to print a int64_t type in C
... hexadecimal.
cppreference.com has a full listing of available macros for all types including intptr_t (PRIxPTR). There are separate macros for scanf, like SCNd64.
A typical definition of PRIu16 would be "hu", so implicit string-constant concatenation happens at compile time.
For your code to ...
How do the likely/unlikely macros in the Linux kernel work and what is their benefit?
I've been digging through some parts of the Linux kernel, and found calls like this:
10 Answers
...
Combining C++ and C - how does #ifdef __cplusplus work?
...f legacy C code. We've started writing in C++, with the intent to eventually convert the legacy code, as well. I'm a little confused about how the C and C++ interact. I understand that by wrapping the C code with extern "C" the C++ compiler will not mangle the C code's names, but I'm no...
How do I log a Python error with debug information?
...g.exception("message")
Output:
ERROR:root:message
Traceback (most recent call last):
File "<stdin>", line 2, in <module>
ZeroDivisionError: integer division or modulo by zero
@Paulo Cheque notes, "be aware that in Python 3 you must call the logging.exception method just inside the ex...
How many GCC optimization levels are there?
..., the default if no optimization level is specified)
-O1 (optimize minimally)
-O2 (optimize more)
-O3 (optimize even more)
-Ofast (optimize very aggressively to the point of breaking standard compliance)
-Og (Optimize debugging experience. -Og enables optimizations that do not interfere...
Why doesn't list have safe “get” method like dictionary?
...accessing list elements (as the len method is very fast). The .get method allows you to query the value associated with a name, not directly access the 37th item in the dictionary (which would be more like what you're asking of your list).
Of course, you can easily implement this yourself:
def sa...
In Flux architecture, how do you manage Store lifecycle?
...
In a Flux app there should only be one Dispatcher. All data flows through this central hub. Having a singleton Dispatcher allows it to manage all Stores. This becomes important when you need Store #1 update itself, and then have Store #2 update itself based on both the Acti...