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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 ...
The tilde operator in Python
...a unary operator (taking a single argument) that is borrowed from C, where all data types are just different ways of interpreting bytes. It is the "invert" or "complement" operation, in which all the bits of the input data are reversed.
In Python, for integers, the bits of the twos-complement repr...
Are braces necessary in one-line statements in JavaScript?
... expands the statement it will be required.
This same practice follows in all C syntax style languages with bracing. C, C++, Java, even PHP all support one line statement without braces. You have to realize that you are only saving two characters and with some people's bracing styles you aren't eve...
Why do people use __(double underscore) so much in C++
...specific, and are slightly more detailed than some others have suggested.
All identifiers that contain a double underscore or start with an underscore followed by an uppercase letter are reserved for the use of the implementation at all scopes, i.e. they might be used for macros.
In addition, all ...
C#: Printing all properties of an object [duplicate]
Is there a method built in to .NET that can write all the properties and such of an object to the console? Could make one using reflection of course, but I'm curious to if this already exists... especially since you can do it in Visual Studio in the Immediate Window. There you can an object name (wh...
Declaring variables inside or outside of a loop
...
The scope of local variables should always be the smallest possible.
In your example I presume str is not used outside of the while loop, otherwise you would not be asking the question, because declaring it inside the while loop would not be an option, since it would not comp...
What is the id( ) function used for?
... Python objects.
Is it the same with memory addresses in C?
Conceptually, yes, in that they are both guaranteed to be unique in their universe during their lifetime. And in one particular implementation of Python, it actually is the memory address of the corresponding C object.
If yes, wh...
融资千万美元后的足记要如何应对“爆款后遗症”? - 资讯 - 清泛网 - 专注C...
...动。但杨柳认为这几个月还是做了不少重要的事:后台从php架构换成Java架构。这些工作前端看不到,但如果不改后台,新功能一个都上不了。
8月底9月初,足记的新版本即将上线,他们并不会推出更多类似“大片”的模式,寻...
How do exceptions work (behind the scenes) in c++
...
Instead of guessing, I decided to actually look at the generated code with a small piece of C++ code and a somewhat old Linux install.
class MyException
{
public:
MyException() { }
~MyException() { }
};
void my_throwing_function(bool throwit)
{
if (...
String concatenation in Ruby
...ficient in term of memory/speed from what I've seen (not measured though). All three methods will throw an uninitialized constant error when ROOT_DIR is nil.
When dealing with pathnames, you may want to use File.join to avoid messing up with pathname separator.
In the end, it is a matter of taste....
