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Why can templates only be implemented in the header file?
...f;
When reading this line, the compiler will create a new class (let's call it FooInt), which is equivalent to the following:
struct FooInt
{
int bar;
void doSomething(int param) {/* do stuff using int */}
}
Consequently, the compiler needs to have access to the implementation of the m...
How can I rename a field for all documents in MongoDB?
...above are: { upsert:false, multi:true }. You need the multi:true to update all your records.
Or you can use the former way:
remap = function (x) {
if (x.additional){
db.foo.update({_id:x._id}, {$set:{"name.last":x.name.additional}, $unset:{"name.additional":1}});
}
}
db.foo.find().forEach...
Access data in package subdirectory
...robust code that can access the subdirectory regardless of where it is installed on the user's system.
6 Answers
...
Readonly Properties in Objective-C?
...ing"; // Notice the underscore prefix of var name.
That’s it, that’s all you need. No muss, no fuss.
Details
As of Xcode 4.4 and LLVM Compiler 4.0 (New Features in Xcode 4.4), you need not mess with the chores discussed in the other answers:
The synthesize keyword
Declaring a variable
Re-...
define() vs. const
...nts: Either using the const keyword or using the define() function:
const FOO = 'BAR';
define('FOO', 'BAR');
The fundamental difference between those two ways is that const defines constants at compile time, whereas define defines them at run time. This causes most of const's disadvantages. Some ...
Python decorators in classes
...ething like this do what you need?
class Test(object):
def _decorator(foo):
def magic( self ) :
print "start magic"
foo( self )
print "end magic"
return magic
@_decorator
def bar( self ) :
print "normal call"
test = Test()
t...
How does collections.defaultdict work?
...
Usually, a Python dictionary throws a KeyError if you try to get an item with a key that is not currently in the dictionary. The defaultdict in contrast will simply create any items that you try to access (provided of course th...
How to return a value from __init__ in Python?
...you want to return an instance variable (or function).
>>> class Foo:
... def __init__(self):
... return 42
...
>>> foo = Foo()
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: __init__() should return None
...
Using “super” in C++
... the first time C++ was standardized.
Dag Bruck proposed this extension, calling the base class "inherited." The proposal mentioned the multiple inheritance issue, and would have flagged ambiguous uses. Even Stroustrup was convinced.
After discussion, Dag Bruck (yes, the same person making the p...
Why is Python running my module when I import it, and how do I stop it?
...program I'm building that can be run in either of 2 ways: the first is to call "python main.py" which prompts the user for input in a friendly manner and then runs the user input through the program. The other way is to call "python batch.py -file- " which will pass over all the friendly input gat...