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How to inherit from a class in javascript?
...t the bottom. I now prefer Object.create(). Object.create is available in all modern browsers.
I should note that Object.create is usually much slower than using new with a function constructor.
//The prototype is just an object when you use `Object.create()`
var Base = {};
//This is how you cre...
How do I show the value of a #define at compile-time?
...ring. When there is more than one component to the argument then they must all be strings so that string concatenation can be applied. The preprocessor can never assume that an unquoted string should be treated as if it were quoted. If it did then:
#define ABC 123
int n = ABC;
would not compile.
...
Python: most idiomatic way to convert None to empty string?
...
If you actually want your function to behave like the str() built-in, but return an empty string when the argument is None, do this:
def xstr(s):
if s is None:
return ''
return str(s)
...
JSON datetime between Python and JavaScript
...
The lambda can be adapted to call the base implementation on non-datetime types, so TypeError can be raised if needed: dthandler = lambda obj: obj.isoformat() if isinstance(obj, datetime) else json.JSONEncoder().default(obj)
– Pascal...
Is there a way to make mv create the directory to be moved to if it doesn't exist?
...ectories don't exist, is there some way to have those directories automatically created, so that you would only have to type
...
Why does running the Flask dev server run itself twice?
...g is the library that supplies Flask with the development server when you call app.run().
See the restart_with_reloader() function code; your script is run again with subprocess.call().
If you set use_reloader to False you'll see the behaviour go away, but then you also lose the reloading function...
How do I import the Django DoesNotExist exception?
...y of the model itself, in this case Answer.
Your problem is that you are calling the get method - which raises the exception - before it is passed to assertRaises. You need to separate the arguments from the callable, as described in the unittest documentation:
self.assertRaises(Answer.DoesNotExis...
Will the Garbage Collector call IDisposable.Dispose for me?
...lizer, and implement IDisposable, that your finalizer needs to explicitly call Dispose.
This is logical, and is what I've always done in the rare situations where a finalizer is warranted.
...
“static const” vs “#define” vs “enum”
...sion for static arrays at function scope; both (2) and (3) can.
Under C99, all of these can be used for local arrays. Technically, using (1) would imply the use of a VLA (variable-length array), though the dimension referenced by 'var' would of course be fixed at size 5.
(1) cannot be used in place...
How do I find all files containing specific text on Linux?
I'm trying to find a way to scan my entire Linux system for all files containing a specific string of text. Just to clarify, I'm looking for text within the file, not in the file name.
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