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Setting PATH environment variable in OSX permanently
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This worked in EL Capitan. Close all the terminals and open a new terminal to check echo $PATH.
– Prem Ananth C
Apr 3 '16 at 12:25
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Python: One Try Multiple Except
...n) as e:
handle_either_of_3rd_4th_or_5th()
except Exception:
handle_all_other_exceptions()
See: http://docs.python.org/tutorial/errors.html
The "as" keyword is used to assign the error to a variable so that the error can be investigated more thoroughly later on in the code. Also note that...
Determine if an object property is ko.observable
...ce) {
if ((instance === null) || (instance === undefined) || (instance.__ko_proto__ === undefined)) return false;
if (instance.__ko_proto__ === ko.dependentObservable) return true;
return ko.isComputed(instance.__ko_proto__); // Walk the prototype chain
};
UPDATE: If you are using KO 2...
When should you use constexpr capability in C++11?
... "function that always returns 5" is breaking or diluting the meaning of "calling a function". There must be a reason, or a need for this capability or it wouldn't be in C++11. Why is it there?
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How to overcome TypeError: unhashable type: 'list'
...used to compare dictionary keys during a dictionary lookup quickly.
Internally, hash() method calls __hash__() method of an object which are set by default for any object.
Converting a nested list to a set
>>> a = [1,2,3,4,[5,6,7],8,9]
>>> set(a)
Traceback (most recent call last...
Download File Using jQuery
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Thanks, this is what I was looking for. I usually use "preventDefault", just left it out above because I was being lazy. ;-)
– Dodinas
Aug 18 '09 at 21:38
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Why doesn't GCC optimize a*a*a*a*a*a to (a*a*a)*(a*a*a)?
...scientific application. One thing I noticed is that GCC will optimize the call pow(a,2) by compiling it into a*a , but the call pow(a,6) is not optimized and will actually call the library function pow , which greatly slows down the performance. (In contrast, Intel C++ Compiler , executable ...
ORA-30926: unable to get a stable set of rows in the source tables
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This is usually caused by duplicates in the query specified in USING clause. This probably means that TABLE_A is a parent table and the same ROWID is returned several times.
You could quickly solve the problem by using a DISTINCT in yo...
How to log PostgreSQL queries?
How to enable logging of all SQL executed by PostgreSQL 8.3?
10 Answers
10
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What is the best way to repeatedly execute a function every x seconds?
...uler.
import sched, time
s = sched.scheduler(time.time, time.sleep)
def do_something(sc):
print("Doing stuff...")
# do your stuff
s.enter(60, 1, do_something, (sc,))
s.enter(60, 1, do_something, (s,))
s.run()
If you're already using an event loop library like asyncio, trio, tkinter,...