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How do you get the logical xor of two variables in Python?
...e not comparing apples to oranges, is "if xor( isApple(x), isApple(y) )" really clearer than "if isApple(x) != isApple(y)" ? Not to me!
– AmigoNico
May 21 '12 at 18:27
109
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How do I count a JavaScript object's attributes? [duplicate]
...ry object in JavaScript derives from — includes many attributes automatically, and the exact set of attributes you get depends on the particular interpreter and what code has executed before yours. So, you somehow have to separate the ones you defined from those you got "for free."
Here's one way...
Extracting bits with a single multiplication
.....
A multiplication is a bunch of shift-and-add operations. The key is to allow overflow to "shift away" the bits we don't need and put the ones we want in the right place.
Multiplication by 4 (00000100) would shift everything left by 2 and get you to a00b0000 . To get the b to move up we need to...
Inserting multiple rows in mysql
...
When loading a table from a text file, use LOAD DATA INFILE. This is usually 20 times faster than using INSERT statements.
Optimizing INSERT Statements
You can find more tips on how to speed up your insert statements on the link above.
...
How can I represent an 'Enum' in Python?
...y3, e.g. you'll need __order__ in python 2).
To use enum34, do $ pip install enum34
To use aenum, do $ pip install aenum
Installing enum (no numbers) will install a completely different and incompatible version.
from enum import Enum # for enum34, or the stdlib version
# from aenum import...
Accessing private member variables from prototype-defined functions
...
No, there's no way to do it. That would essentially be scoping in reverse.
Methods defined inside the constructor have access to private variables because all functions have access to the scope in which they were defined.
Methods defined on a prototype are not defin...
How to calculate a time difference in C++
...turns the CPU time consumed by the program. So if the program is run in parallel the time returned by the function would be the accumulated of the time spent on all CPUs, rather than the time elapsed cplusplus.com/reference/ctime/clock
– Ameer Jewdaki
Aug 3 '1...
How to drop all tables in a SQL Server database?
...y tables.
I found that code that works and does everything you try (delete all tables from your database):
DECLARE @Sql NVARCHAR(500) DECLARE @Cursor CURSOR
SET @Cursor = CURSOR FAST_FORWARD FOR
SELECT DISTINCT sql = 'ALTER TABLE [' + tc2.TABLE_SCHEMA + '].[' + tc2.TABLE_NAME + '] DROP [' + rc1.C...
Which $_SERVER variables are safe?
...ttacker can also control and is therefore a source of an attack. This is called a "tainted" variable, and is unsafe.
2 An...
Why should eval be avoided in Bash, and what should I use instead?
...rintln. We could, of course, just redirect the output of println on each call, but for the sake of example, we're not going to do that. We'll need to use eval, since variables can't be used to redirect output.
function println
{
eval printf "$2\n" "${@:3}" $1
}
function error
{
println '...