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What belongs in an educational tool to demonstrate the unwarranted assumptions people make in C/C++?
...|),
the ternary conditional operator (?:), and
the comma operator (,)
is Unspecified
For example
int Hello()
{
return printf("Hello"); /* printf() returns the number of
characters successfully printed by it
*/
}
...
Python `if x is not None` or `if not x is None`?
I've always thought of the if not x is None version to be more clear, but Google's style guide and PEP-8 both use if x is not None . Is there any minor performance difference (I'm assuming not), and is there any case where one really doesn't fit (making the other a clear winner for my convent...
How does the Windows Command Interpreter (CMD.EXE) parse scripts?
...differences between batch and command line mode.
Batch Line Parser:
Here is a brief overview of phases in the batch file line parser:
Phase 0) Read Line:
Phase 1) Percent Expansion:
Phase 2) Process special characters, tokenize, and build a cached command block: This is a complex process that i...
Is there a difference between “==” and “is”?
...
is will return True if two variables point to the same object, == if the objects referred to by the variables are equal.
>>> a = [1, 2, 3]
>>> b = a
>>> b is a
True
>>> b == a
True
# Mak...
What is the difference between is_a and instanceof?
I am aware that instanceof is an operator and that is_a is a method.
9 Answers
9
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Why does the is operator return false when given null?
It seems to me that the is operator is a bit inconsistent.
7 Answers
7
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AI2 Keep Awake
...he lifespan of the device battery will be significantly reduced by using this extension. Do not set WakeLocks if you do not really need them, use them as rarely as possible and release them as soon as possible. If actions are to be performed only occasionally, it is not necessary for the CPU ...
What are the differences between virtual memory and physical memory?
...
Virtual memory is, among other things, an abstraction to give the programmer the illusion of having infinite memory available on their system.
Virtual memory mappings are made to correspond to actual physical addresses. The operating syste...
Difference between is and as keyword
Please tell what is the difference between is and as keyword in C#
14 Answers
14
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What part of Hindley-Milner do you not understand?
...must be true in order to guarantee the [below].
: means has type
∈ means is in. (Likewise ∉ means "is not in".)
Γ is usually used to refer to an environment or context; in this case it can be thought of as a set of type annotations, pairing an identifier with its type. Therefore x : σ ∈ Γ ...