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How do I focus on one spec in jasmine.js?
... its a good tip, but currently it isn't in jasmine. this is allowed by test runners like karma. for more info read on: github.com/pivotal/jasmine/pull/309
– p1100i
Aug 12 '14 at 9:08
...
Python: fastest way to create a list of n lists
...
The probably only way which is marginally faster than
d = [[] for x in xrange(n)]
is
from itertools import repeat
d = [[] for i in repeat(None, n)]
It does not have to create a new int object in every iteration and is about 15 % faster on my machine.
Edi...
How can i tell if an object has a key value observer attached
...
Put a try catch around your removeObserver call
@try{
[someObject removeObserver:someObserver forKeyPath:somePath];
}@catch(id anException){
//do nothing, obviously it wasn't attached because an exception was thrown
}
...
How to convert list of tuples to multiple lists?
...
xs, ys = [x for x, y in zs], [y for x, y in zs]
return xs, ys
if __name__ == '__main__':
from timeit import timeit
setup_string='''\
N = 2000000
xs = list(range(1, N))
ys = list(range(N+1, N*2))
zs = list(zip(xs, ys))
from __main__ import t1, t2, t3
'''
print(f'zip:\t\t{timeit(...
How to get the original value of an attribute in Rails
...
Before rails 5.1
Appending _was to your attribute will give you the previous value.
For rails 5.1+
Copied from Lucas Andrade's answer below: https://stackoverflow.com/a/50973808/9359123
Appending _was is deprecated in rails 5.1, now you should ap...
How do I pass extra arguments to a Python decorator?
... it needs to return another function which is the actual decorator:
def my_decorator(param):
def actual_decorator(func):
print("Decorating function {}, with parameter {}".format(func.__name__, param))
return function_wrapper(func) # assume we defined a wrapper somewhere
ret...
Arduino Sketch upload issue - avrdude: stk500_recv(): programmer is not responding
...it works. I figured the packets were some attempt at a hand-shake. So basically, I solved it using Google, patience and futzing around with the board!
– hoipolloi
Jan 12 '14 at 18:16
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Finding the source code for built-in Python functions?
...out what file a particular module or function is implemented in you can usually print the __file__ attribute. Alternatively, you may use the inspect module, see the section Retrieving Source Code in the documentation of inspect.
For built-in classes and methods this is not so straightforward since ...
What are the differences between -std=c++11 and -std=gnu++11?
...oid extensions because I don't recommend doing anything that isn't specifically defined by the Standard... but even then, "violates" is a strange and loaded term, when a lot of these extensions are, to use Standardese, just implementation-defining or specifying things that the Standard is silent on ...
Can Flask have optional URL parameters?
...
You can try pip install flask_optional_routes. I created a pip for the functionality you are requesting b/c I needed it as well. The code is located at: github.com/sudouser2010/flask_optional_routes.
– sudouser2010
...