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What is the difference between class and instance attributes?
...just look in each instance's __dict__ and the class's __dict__. It just usually doesn't matter very much whether immutable types are shared or not.
– abarnert
Oct 29 '14 at 22:58
1...
What can you do in MSIL that you cannot do in C# or VB.NET? [closed]
All code written in .NET languages compiles to MSIL, but are there specific tasks / operations that you can do only using MSIL directly?
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How do I use itertools.groupby()?
I haven't been able to find an understandable explanation of how to actually use Python's itertools.groupby() function. What I'm trying to do is this:
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How do I return multiple values from a function? [closed]
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Well, the design rationale for namedtuple is having a smaller memory footprint for mass results (long lists of tuples, such as results of DB queries). For individual items (if the function in question is not called often) dictionaries and classes are just fine as well. But namedtu...
Extract elements of list at odd positions
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Solution
Yes, you can:
l = L[1::2]
And this is all. The result will contain the elements placed on the following positions (0-based, so first element is at position 0, second at 1 etc.):
1, 3, 5
so the result (actual numbers) will be:
2, 4, 6
Explanation
The [1::2]...
Removing duplicates from a list of lists
... much easier that it offers good returns on efforts. But sometimes (essentially for "tragically crucial bottlenecks" in deep inner loops of code that's pushing the boundaries of performance limits) one may need to go into much more detail, providing probability distributions, deciding which performa...
Trusting all certificates using HttpClient over HTTPS
... problem, I can't seem to find an example anywhere that works for me. Basically, I want my client to accept any certificate (because I'm only ever pointing to one server) but I keep getting a javax.net.ssl.SSLException: Not trusted server certificate exception.
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Why does struct alignment depend on whether a field type is primitive or user-defined?
... The documentation of StructLayoutAttribute is pretty interesting. Basically, only blittable types are controlled through StructLayout in managed memory. Interesting, never knew that.
– Michael Stum♦
Jul 15 '14 at 7:01
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Javascript: Round up to the next multiple of 5
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const fn = _num =>{
return Math.round(_num)+ (5 -(Math.round(_num)%5))
}
reason for using round is that expected input can be a random number.
Thanks!!!
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How to add column if not exists on PostgreSQL?
...statement:
DO $$
BEGIN
BEGIN
ALTER TABLE <table_name> ADD COLUMN <column_name> <column_type>;
EXCEPTION
WHEN duplicate_column THEN RAISE NOTICE 'column <column_name> already exists in <table_name>.';
END;
END;
$$
...