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Python: Is it bad form to raise exceptions within __init__?
...t have been designed with exception safety in mind, the destructor is not called if an exception is thrown in the constructor of an object (meaning that the initialization of the object is incomplete). This is often not the case in scripting languages, such as Python. For example, the following code...
Is there a MySQL option/feature to track history of changes to records?
...ant to audit the changes to the data - who did what and when?", you can usually use audit tables (as per the trigger example Keethanjan posted). I'm not a huge fan of triggers, but it has the great benefit of being relatively painless to implement - your existing code doesn't need to know about the ...
Calling a class function inside of __init__
...
Call the function in this way:
self.parse_file()
You also need to define your parse_file() function like this:
def parse_file(self):
The parse_file method has to be bound to an object upon calling it (because it's not a ...
Unzip a file with php
...e it out by yourself. On the other hand, the fact that this code could actually be published online somewhere as the correct way to unzip a file is a bit frightening.
PHP has built-in extensions for dealing with compressed files. There should be no need to use system calls for this. ZipArchivedocs ...
Xcode/Simulator: How to run older iOS version?
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As for weak linking, will this still install on an older device? I tried a while ago and came to the conclusion (as well as others) that if you want iAds, you need to be 4.0 minimum.
– ingh.am
Nov 23 '10 at 23:24
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What's the use of ob_start() in php?
...Think of ob_start() as saying "Start remembering everything that would normally be outputted, but don't quite do anything with it yet."
For example:
ob_start();
echo("Hello there!"); //would normally get printed to the screen/output to browser
$output = ob_get_contents();
ob_end_clean();
There a...
Suppressing deprecated warnings in Xcode
With all the SDKs floating around, it's handy to be able to build for multiple SDKs and platforms. However, bouncing from 3.2 to 3.0 and even occasionally 2.x, I frequently get deprecated warnings involving methods that have changed or been superseded:
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Is “else if” a single keyword?
...er to Can you start a class name with a numeric digit? that spaces are not allowed in identifiers and so therefore else if can not be a single keyword but must be two separate keywords.
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impr...
How can I represent an 'Enum' in Python?
...y3, e.g. you'll need __order__ in python 2).
To use enum34, do $ pip install enum34
To use aenum, do $ pip install aenum
Installing enum (no numbers) will install a completely different and incompatible version.
from enum import Enum # for enum34, or the stdlib version
# from aenum import...
How to log a method's execution time exactly in milliseconds?
...ed for being a bad example. See also the related answer that explains this all in more detail: stackoverflow.com/a/30363702/43615
– Thomas Tempelmann
Jun 4 '16 at 13:36
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