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When is “i += x” different from “i = i + x” in Python?
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This depends entirely on the object i.
+= calls the __iadd__ method (if it exists -- falling back on __add__ if it doesn't exist) whereas + calls the __add__ method1 or the __radd__ method in a few cases2.
From an API perspective, __iadd__ is supposed to be used fo...
What is the size of an enum in C?
...set of enum values, but I need each enum value to be 64 bits wide. If I recall correctly, an enum is generally the same size as an int; but I thought I read somewhere that (at least in GCC) the compiler can make the enum any width they need to be to hold their values. So, is it possible to have an e...
Microsoft.Jet.OLEDB.4.0' provider is not registered on the local machine
...lution for this problem. The issue I described in my question occured basically due to the incompatibility of the Microsoft.Jet.OLEDB.4.0 driver in 64 bit OS.
So if we are using Microsoft.Jet.OLEDB.4.0 driver in a 64 bit server, we have to force our application to build in in 32 bit mode (This is ...
How to convert CFStringRef to NSString?
...n objects with +1 reference counts, meaning that they need to be released (all CF[Type]Create format functions do this).
The nice thing is that in Cocoa you can safely use autorelease or release to free them up.
share
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Creating stored procedure and SQLite?
...than in a separate SQL engine process. So it makes more sense to implement all your business logic including what would have been SP code in the host language.
You can however extend SQLite with your own user defined functions in the host language (PHP, Python, Perl, C#, Javascript, Ruby etc). You ...
Can I use Objective-C blocks as properties?
... @CharlieMonroe - Yes you are probably right, but dont you need a dealloc implementation to nil or release the block property without ARC? (its been a while since I used non-ARC)
– Robert
Mar 31 '13 at 21:58
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ssl_error_rx_record_too_long and Apache SSL [closed]
...default_:443>
Error code: ssl_error_rx_record_too_long
This usually means the implementation of SSL on your server is not correct. The error is usually caused by a server side problem which the server administrator will need to investigate.
Below are some things we recommend trying....
rgdal package installation
...liam Kyngesburye at http://www.kyngchaos.com/ may be used for
source installs on OSX.
As you seem to be under Linux, you always build package from source, so you will have to install the corresponding libraries on your system. If you are under Mint, Ubuntu or another Debian derivative, you can d...
What is the purpose of willSet and didSet in Swift?
... for instance to notify other objects that the property just changed. When all you have is get/set, you need another field to hold the value. With willSet and didSet, you can take action when the value is modified without needing another field. For instance, in that example:
class Foo {
var myP...
Joins are for lazy people?
...r developer who claimed to me that JOINs (SQL) are useless. This is technically true but he added that using joins is less efficient than making several requests and link tables in the code (C# or Java).
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