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Understanding scala enumerations
...er Value representing the individual elements of the enumeration (it's actually an inner class, but the difference doesn't matter here).
Thus object WeekDay inherits that type member. The line type WeekDay = Value is just a type alias. It is useful, because after you import it elsewhere with import...
Easy pretty printing of floats in python?
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It's an old question but I'd add something potentially useful:
I know you wrote your example in raw Python lists, but if you decide to use numpy arrays instead (which would be perfectly legit in your example, because you seem to be dealing with arrays of numbers), there is ...
How to JSON serialize sets?
...s.
As shown in the json module docs, this conversion can be done automatically by a JSONEncoder and JSONDecoder, but then you would be giving up some other structure you might need (if you convert sets to a list, then you lose the ability to recover regular lists; if you convert sets to a dictionar...
target=“_blank” vs. target=“_new”
...or window when the user clicks on the link.
Using target="_new" is technically invalid according to the specifications, but as far as I know every browser will behave the same way:
it will search for a tab or window with the context name "_new"
if a "_new" tab/window is found, then the URL is loa...
Check if all elements in a list are identical
... = next(iterator)
except StopIteration:
return True
return all(first == rest for rest in iterator)
One-liner:
def checkEqual2(iterator):
return len(set(iterator)) <= 1
Also one-liner:
def checkEqual3(lst):
return lst[1:] == lst[:-1]
The difference between the 3 versi...
Calling a base class's classmethod in Python
...asses, which derive from object. (at least in Python 2, but in Py3 I think all classes are new-style, IIRC) Otherwise you have to do Base.do(self, ...), I think, thereby hard-coding the name of the superclass.
– David Z
Jun 11 '14 at 19:29
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Update multiple rows in same query using PostgreSQL
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This is wrong... You will update all rows, even if it is not '123' nor '345'. You should use WHERE column_b IN ('123','456')...
– MatheusOl
Sep 14 '13 at 3:54
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Draw line in UIView
...re are no errors - I wrote it without Xcode):
UIView *lineView = [[UIView alloc] initWithFrame:CGRectMake(0, 200, self.view.bounds.size.width, 1)];
lineView.backgroundColor = [UIColor blackColor];
[self.view addSubview:lineView];
[lineView release];
// You might also keep a reference to this view
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Access an arbitrary element in a dictionary in Python
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for a non-destructive popitem you can make a (shallow) copy: key, value = dict(d).popitem()
– Pelle
Jan 31 '18 at 10:35
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List of special characters for SQL LIKE clause
What is the complete list of all special characters for a SQL (I'm interested in SQL Server but other's would be good too) LIKE clause?
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