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Understanding Python's “is” operator
...e value.
From the documentation for the is operator:
The operators is and is not test for object identity: x is y is true if and only if x and y are the same object.
Use the == operator instead:
print(x == y)
This prints True. x and y are two separate lists:
x[0] = 4
print(y) # prints [1...
Does the 'mutable' keyword have any purpose other than allowing the variable to be modified by a con
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It allows the differentiation of bitwise const and logical const. Logical const is when an object doesn't change in a way that is visible through the public interface, like your locking example. Another example would be a class that computes a value the first time it is...
Java Name Hiding: The Hard Way
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You can cast a null to the type and then invoke the method on that (which will work, since the target object isn't involved in invocation of static methods).
((net.foo.X) null).doSomething();
This has the benefits of
being side-effect free (a problem w...
How to replace spaces in file names using a bash script
...end a safe solution to recursively replace spaces with underscores in file and directory names starting from a given root directory? For example:
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How do you check “if not null” with Eloquent?
...null at deleted field, so I changed this into whereNull('deleted_at') and I got my query running.
– Tarunn
Jun 19 '15 at 12:45
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HTML select form with option to enter custom value
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HTML5 has a built-in combo box. You create a text input and a datalist. Then you add a list attribute to the input, with a value of the id of the datalist.
Update: As of March 2019 all major browsers (now including Safari 12.1 and iOS Safari 12.3) support datalist to the level ne...
Will iOS launch my app into the background if it was force-quit by the user?
...ng the content-available flag on a push notification. I have the fetch and remote-notification UIBackgroundModes enabled.
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Python time measure function
I want to create a python function to test the time spent in each function and print its name with its time, how i can print the function name and if there is another way to do so please tell me
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When should assertions stay in production code? [closed]
... not become outdated. They document which theoretical states are intended, and which states should not occur. If code is changed so states allowed change, the developer is soon informed and needs to update the assertion.
sha...
Include all existing fields and add new fields to document
...ne a $project aggregation stage where I can instruct it to add a new field and include all existing fields, without having to list all the existing fields.
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