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In what cases do I use malloc and/or new?
...ou should call free and when you use the new operator you should pair with delete and it is a mistake to mix the two (e.g. Calling free() on something that was created with the new operator), but I'm not clear on when I should use malloc / free and when I should use new / delete in m...
Using ZXing to create an Android barcode scanning app [duplicate]
...);
intent.putExtra("SCAN_MODE", "QR_CODE_MODE");
startActivityForResult(intent, 0);
}
};
public void onActivityResult(int requestCode, int resultCode, Intent intent) {
if (requestCode == 0) {
if (resultCode == RESULT_OK) {
String contents = intent.getStri...
Best practice for Python assert
...hanZeroException(Exception):
pass
class variable(object):
def __init__(self, value=0):
self.__x = value
def __set__(self, obj, value):
if value < 0:
raise LessThanZeroException('x is less than zero')
self.__x = value
def __get__(self, obj, ...
Difference between HashMap, LinkedHashMap and TreeMap
...ee classes implement the Map interface and offer mostly the same functionality. The most important difference is the order in which iteration through the entries will happen:
HashMap makes absolutely no guarantees about the iteration order. It can (and will) even change completely when new element...
Accessing class variables from a list comprehension in the class definition
How do you access other class variables from a list comprehension within the class definition? The following works in Python 2 but fails in Python 3:
...
Why is the default value of the string type null instead of an empty string?
It's quite annoying to test all my strings for null before I can safely apply methods like ToUpper() , StartWith() etc...
...
How to prevent Node.js from exiting while waiting for a callback?
...re empty. A callback is added to an event queue when a call such as
emmiter1.on('this_event',callback).
has executed. This call is part of the code written by the module developer .
If a module is a quick port from a synchronous/blocking version, this may not happen til some part of the oper...
Breadth First Vs Depth First
...ese two terms differentiate between two different ways of walking a tree.
It is probably easiest just to exhibit the difference. Consider the tree:
A
/ \
B C
/ / \
D E F
A depth first traversal would visit the nodes in this order
A, B, D, C, E, F
Notice that you go all the w...
__proto__ VS. prototype in JavaScript
...e is the object that is used to build __proto__ when you create an object with new:
( new Foo ).__proto__ === Foo.prototype;
( new Foo ).prototype === undefined;
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Differences between Perl and PHP [closed]
...to learn Perl 5 and as I have only used PHP until now, I wanted to know a bit about how the languages differ from each other.
...