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Objective-C ARC: strong vs retain and weak vs assign
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@Pascal: weak references aren't allowed in deployment targets where the os is not 5.0 or higher. So for older projects you can still use assign, but if you move to newer versions you have to switch to weak
– Mattia
Feb...
How to automatically generate a stacktrace when my program crashes
... the GCC compiler. When my C++ program crashes I would like it to automatically generate a stacktrace.
28 Answers
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What does Python's eval() do?
...less until you find a need for it. It is used on sites like codepad.org to allow you to execute scripts in a test environment. eval() can also be used to execute highly-dynamic code, but you should make yourself fully aware of the security and performance risks before using it.
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get current url in twig template?
...ttributes.get('_route_params')) %}
The app global view variable contains all sorts of useful shortcuts, such as app.session and app.security.token.user, that reference the services you might use in a controller.
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Is there a simple, elegant way to define singletons? [duplicate]
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I don't really see the need, as a module with functions (and not a class) would serve well as a singleton. All its variables would be bound to the module, which could not be instantiated repeatedly anyway.
If you do wish to use a cla...
Store JSON object in data attribute in HTML jQuery
...in the text just use $('#myElement').data('key',jsonObject);
it won't actually be stored in the html, but if you're using jquery.data, all that is abstracted anyway.
To get the JSON back don't parse it, just call:
var getBackMyJSON = $('#myElement').data('key');
If you are getting [Object Objec...
Principal component analysis in Python
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Months later, here's a small class PCA, and a picture:
#!/usr/bin/env python
""" a small class for Principal Component Analysis
Usage:
p = PCA( A, fraction=0.90 )
In:
A: an array of e.g. 1000 observations x 20 variables, 1000 rows x 20 colum...
How to get a function name as a string?
In Python, how do I get a function name as a string, without calling the function?
12 Answers
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What is the __del__ method, How to call it?
...is used, probably not like that: obj1.del() . So, my questions is how to call the __del__ method?
5 Answers
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How can I tell gcc not to inline a function?
Say I have this small function in a source file
8 Answers
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