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What is the purpose of the word 'self'?
What is the purpose of the self word in Python? I understand it refers to the specific object created from that class, but I can't see why it explicitly needs to be added to every function as a parameter. To illustrate, in Ruby I can do this:
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Best way to detect that HTML5 is not supported
The standard way to deal with situations where the browser does not support the HTML5 <canvas> tag is to embed some fallback content like:
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How to get certain commit from GitHub project
... Next, change into the newly cloned repository:
cd facebook-ios-sdk
... and use git checkout <COMMIT> to change to the right commit:
git checkout 91f25642453
That will give you a warning, since you're no longer on a branch, and have switched directly to a particular version. (This is kn...
How to stop /#/ in browser with react-router?
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For the versions 1, 2 and 3 of react-router, the correct way to set the route to URL mapping scheme is by passing a history implementation into the history parameter of <Router>. From the histories documentation:
In a nutshell, a history...
Possible to do a MySQL foreign key to one of two possible tables?
...table.
Polymorphic Associations are supported by frameworks such as Rails and Hibernate. But they explicitly say that you must disable SQL constraints to use this feature. Instead, the application or framework must do equivalent work to ensure that the reference is satisfied. That is, the value ...
Word wrap for a label in Windows Forms
...ically (only width). To get this right you will need to subclass the label and include vertical resize logic.
Basically what you need to do in OnPaint is:
Measure the height of the text (Graphics.MeasureString).
If the label height is not equal to the height of the text set the height and return....
What's the point of malloc(0)?
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The C standard (C17 7.22.3/1) says:
If the size of the space requested is zero, the behavior is implementation defined:
either a null pointer is returned, or the behavior is as if the size were some
nonzero value, except that...
MongoDB/NoSQL: Keeping Document Change History
...his approach is fine though when you're dealing with small-sized documents and/or don't update documents very often.
Only store changes in a new version
Another approach would be to store only the changed fields in a new version. Then you can 'flatten' your history to reconstruct any version of th...
PHP: Storing 'objects' inside the $_SESSION
I just figured out that I can actually store objects in the $_SESSION and I find it quite cool because when I jump to another page I still have my object. Now before I start using this approach I would like to find out if it is really such a good idea or if there are potential pitfalls involved....
Why are my PowerShell scripts not running?
I wrote a simple batch file as a PowerShell script, and I am getting errors when they run.
9 Answers
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