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Sending a message to nil in Objective-C
...ize(); ++i){
System.out.println(list.get(i).toString());
}
}
Now, if you call that method like so: someObject.foo(NULL); you're going to probably get a NullPointerException when it tries to access list, in this case in the call to list.size(); Now, you'd probably never call someObject....
Surrogate vs. natural/business keys [closed]
...
Now, after reading a lot about surrogate keys and natural keys, I think using surrogate keys is better. But, on my database, natural keys (a NVARCHAR(20)) must be unique. I don't understand how I can get more speed if I need ...
Browser doesn't scale below 400px?
...to the right instead of to the bottom
Resize the inspector panel - you can now make the browser area really small (down to 0px)
Update: Chrome now allows you to arrange the inspector windows vertically when docked to the right! This really improves the layout.
The HTML and CSS panels fit really...
.prop() vs .attr()
...
@Neal: If you want to know what properties DOM elements have and how attributes may seed their values, keep these links to hand: The DOM2 HTML specification, the DOM2 spec, and DOM3 spec. The indexes in each case are excellent and link you straight...
Is it good practice to NULL a pointer after deleting it?
... Imagaine a mainainer comming back a year later and seeing foo deleted. He now believes he can re-use the pointer unfortunately he may miss the second delete (it may not even be in the same function) and now the re-use of the pointer now gets trashed by the second delete. Any access after the second...
Upgrading Node.js to latest version
So, I have Node.js installed and now when I tried to install Mongoosejs I got an error telling me that I don't have the needed version of Node.js (I have v0.4.11 and v0.4.12 is needed).
...
Hidden features of Eclipse [closed]
...y = new |
and then I pushed Ctrl-Space to complete the constructor call. Now I type:
new Display()|
and press Ctrl-2 L, which results in:
Display display = new Display()|
This really speeds things up. (Ctrl-2 F does the same, but assigns to a new field rather than a new variable.)
Another g...
What is the most robust way to force a UIView to redraw?
...hy. the subclass in question gets passed the data and it's drawRect method now has everything it needs to render.
5 Answers...
explicit casting from super class to subclass
... you're essentially telling the compiler "trust me. I'm a professional, I know what I'm doing and I know that although you can't guarantee it, I'm telling you that this animal variable is definitely going to be a dog."
Since the animal isn't actually a dog (it's an animal, you could do Animal anima...
What is the difference between include and extend in Ruby?
...class (i.e. the singleton class)
e.g.
if you call Klazz.extend(Mod), now Klazz has Mod's methods (as class methods)
if you call obj.extend(Mod), now obj has Mod's methods (as instance methods), but no other instance of of obj.class has those methods added.
extend is a public method
include -...