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Does JavaScript have “Short-circuit” evaluation?
... in times of JIT-compiling-magic in javascript implementations, one does really want to know if something is "the standard" , or potentially subject to the implementation. The way a condition statement with Binary Logical Operators is evaluated and (short-curcuit) is a standard behavior ecma-interna...
What's wrong with nullable columns in composite primary keys?
...
Primary keys are for uniquely identifying rows. This is done by comparing all parts of a key to the input.
Per definition, NULL cannot be part of a successful comparison. Even a comparison to itself (NULL = NULL) will fail. This means a key containing NULL would not work.
Additonally, NULL is al...
e.printStackTrace equivalent in python
... = logging.getLogger()
logger.setLevel(logging.DEBUG)
def f():
a = { 'foo': None }
# the following line will raise KeyError
b = a['bar']
def g():
f()
try:
g()
except Exception as e:
logger.error(str(e), exc_info=True)
And it will output:
'bar'
Traceback (most recent cal...
What is the difference between instanceof and Class.isAssignableFrom(…)?
...s Y which extends Z which extends A), results might be different.
it is usually advised to write the code first picking one of the operators (the most convenient) and then profile your code to check if there are a performance bottleneck. Maybe this operator is negligible in the context of your code,...
How do I Moq a method that has an optional argument in its signature without explicitly specifying i
...ice right now is to explicitly include the bool parameter in the setup for Foo.
I don't think it defeats the purpose of specifying a default value. The default value is a convenience for calling code, but I think that you should be explicit in your tests. Say you could leave out specifying the bool...
Is it necessary to explicitly remove event handlers in C#
...ng:
using System;
public class Publisher
{
public event EventHandler Foo;
public void RaiseFoo()
{
Console.WriteLine("Raising Foo");
EventHandler handler = Foo;
if (handler != null)
{
handler(this, EventArgs.Empty);
}
else
...
Automapper - how to map to constructor parameters instead of property setters
...
Use ConstructUsing
this will allow you to specify which constructor to use during the mapping. but then all of the other properties will be automatically mapped according to the conventions.
Also note that this is different from ConvertUsing in that con...
How to use php serialize() and unserialize()
... and Javascript can only communicate via strings. You can pass the string "foo" very easily to Javascript. You can pass the number 1 very easily to Javascript. You can pass the boolean values true and false easily to Javascript. But how do you pass this array to Javascript?
Array ( [1] => elem 1...
How to declare a global variable in a .js file
I need a few global variables that I need in all .js files.
5 Answers
5
...
Set a persistent environment variable from cmd.exe
...ferent windows machines, but I don't want to be bothered changing them manually by getting on the properties screen of "My Computer"
...