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How update the _id of one MongoDB Document?
I want update an _id field of one document. I know it's not a really good pratice. But with some technical reason, I need update it. If I try to update it I get:
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On logout, clear Activity history stack, preventing “back” button from opening logged-in-only Activi
All activities in my application require a user to be logged-in to view. Users can log out from almost any activity. This is a requirement of the application. At any point if the user logs-out, I want to send the user to the Login Activity . At this point I want this activity to be at the bottom of...
how to break the _.each function in underscore.js
...t provide to escape the loop (other than throwing an exception).
However, all hope is not lost! You can use the Array.every method. :)
From that link:
every executes the provided callback function once for each element present in the array until it finds one where callback returns a false valu...
What's the difference between hard and soft floating point numbers?
...t float) in accuracy-critical parts and fast (hard float) in parts where small deviations don't matter.
– PhilLab
May 29 '17 at 12:18
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How to len(generator()) [duplicate]
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Generators have no length, they aren't collections after all.
Generators are functions with a internal state (and fancy syntax). You can repeatedly call them to get a sequence of values, so you can use them in loop. But they don't contain any elements, so asking for the length of ...
Flattening a shallow list in Python [duplicate]
...st of iterables with a list comprehension, or failing that, what would you all consider to be the best way to flatten a shallow list like this, balancing performance and readability?
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What is the most pythonic way to check if an object is a number?
...and is not iterable" could be a good definition in some cases. But,
you really need to ask yourself, what it is that you're asking that what you want to consider "a number" must definitely be able to do, and what it must absolutely be unable to do -- and check.
This may also be needed in 2.6 or la...
Is there a TRY CATCH command in Bash
... writing a shell script and need to check that a terminal app has been installed. I want to use a TRY/CATCH command to do this unless there is a neater way.
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What is a clean, pythonic way to have multiple constructors in Python?
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Actually None is much better for "magic" values:
class Cheese():
def __init__(self, num_holes = None):
if num_holes is None:
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Now if you want complete freedom of adding more parameters:
class Cheese...
Which characters are valid in CSS class names/selectors?
What characters/symbols are allowed within the CSS class selectors?
I know that the following characters are invalid , but what characters are valid ?
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