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How to check if object has any properties in JavaScript?
...d Apr 20 '10 at 6:49
Daniel VassalloDaniel Vassallo
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Using backticks around field names
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To me it makes a lot of sense to use them at all times when dealing with field names.
Firstly, once you get into the habit, it doesn't hurt to just hit the backtick key.
Secondly, to me, it makes it easier to see what exactly are the fields in your query, and what ar...
What would be C++ limitations compared C language? [closed]
...uestion which asks about a generics library for C - the questioner specifically states that they do not want to use C++.
C is a complete programming language. C is not an arbitrary subset of C++. C is not a subset of C++ at all.
This is valid C:
foo_t* foo = malloc ( sizeof(foo_t) );
To make ...
How can I convert a string to a number in Perl?
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You don't need to convert it at all:
% perl -e 'print "5.45" + 0.1;'
5.55
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Mediator Vs Observer Object-Oriented Design Patterns
...-to-many dependency between objects so that when one object changes state, all its dependents are notified and updated automatically.
The Mediator pattern:
Define an object that encapsulates how a set of objects interact. Mediator promotes loose coupling by keeping objects from referring to each o...
Block Comments in Clojure
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Actually, there is a way!
(comment
(defn hey []
("Hey there!"))
Check me out!
)
Just wrap your comments in (comment ..) :)
Have fun!
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When should I make explicit use of the `this` pointer?
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Usually, you do not have to, this-> is implied.
Sometimes, there is a name ambiguity, where it can be used to disambiguate class members and local variables. However, here is a completely different case where this-> is e...
Why use the 'ref' keyword when passing an object?
...nt to change what the object is:
TestRef t = new TestRef();
t.Something = "Foo";
DoSomething(ref t);
void DoSomething(ref TestRef t)
{
t = new TestRef();
t.Something = "Not just a changed t, but a completely different TestRef object";
}
After calling DoSomething, t does not refer to the origin...
Catching multiple exception types in one catch block
...fining the exceptions). Even given that there are exceptions you want to "fall through", you should still be able to define a hierarchy to match your needs.
abstract class MyExceptions extends Exception {}
abstract class LetterError extends MyExceptions {}
class AError extends LetterError {}
cla...
How do I pass extra arguments to a Python decorator?
...to wrap my head around.
class NiceDecorator:
def __init__(self, param_foo='a', param_bar='b'):
self.param_foo = param_foo
self.param_bar = param_bar
def __call__(self, func):
def my_logic(*args, **kwargs):
# whatever logic your decorator is supposed to i...