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How do I select a random value from an enumeration?
...
Use Enum.GetValues to retrieve an array of all values. Then select a random array item.
static Random _R = new Random ();
static T RandomEnumValue<T> ()
{
var v = Enum.GetValues (typeof (T));
return (T) v.GetValue (_R.Next(v.Length));
}
Test:
for (in...
How to print instances of a class using print()?
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>>> class Test:
... def __repr__(self):
... return "Test()"
... def __str__(self):
... return "member of Test"
...
>>> t = Test()
>>> t
Test()
>>> print(t)
member of Test
The __str__ method is what h...
Number of processors/cores in command line
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Make sure to nproc --all for all installed Processing Units. Without --all, nproc only shows Processing Units available to the current process. Read the man page for more details. MMV.
– JamesThomasMoon1979
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Example of multipart/form-data
...6 is two hyphens shorter then the actual boundaries in the data. This is really, really hard to see with all the hyphens strung together.
– Fake Name
Jun 2 '17 at 6:39
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How to play audio?
... has a audio format compatibility table. new Audio() can play WAV files in all browsers except Internet Explorer.
– Rory O'Kane
Mar 15 '15 at 14:18
311
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Standard alternative to GCC's ##__VA_ARGS__ trick?
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It is possible to avoid the use of GCC's ,##__VA_ARGS__ extension if you are willing to accept some hardcoded upper limit on the number of arguments you can pass to your variadic macro, as described in Richard Hansen's answer to this question. If you do not want to hav...
Docker how to change repository name or rename image?
...host OS and Docker version? I suspect that something about your Docker installation is modifying the tag instruction.
– Andy
Feb 18 '16 at 2:41
27
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How do you trigger a block after a delay, like -performSelector:withObject:afterDelay:?
Is there a way to call a block with a primitive parameter after a delay, like using performSelector:withObject:afterDelay: but with an argument like int / double / float ?
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How can I count the occurrences of a list item?
...1, 4, 1].count(1)
3
Don't use this if you want to count multiple items. Calling count in a loop requires a separate pass over the list for every count call, which can be catastrophic for performance. If you want to count all items, or even just multiple items, use Counter, as explained in the othe...
Setting a property by reflection with a string value
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You can use Convert.ChangeType() - It allows you to use runtime information on any IConvertible type to change representation formats. Not all conversions are possible, though, and you may need to write special case logic if you want to support conversions from t...