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if A vs if A is not None:
...
The statement
if A:
will call A.__nonzero__() (see Special method names documentation) and use the return value of that function. Here's the summary:
object.__nonzero__(self)
Called to implement truth value testing and the built-in operation ...
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 it the significance of the Javascript constructor property?
...the constructor property is used in a few places. However, I think the overall gist still applies. Thanks to T. J. Crowder for pointing that out in the comments, and please read his answer for a fuller picture of the current situation.
Original answer
The constructor property makes absolutely no pra...
Best practice for Python assert
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To be able to automatically throw an error when x become less than zero throughout the function. You can use class descriptors. Here is an example:
class LessThanZeroException(Exception):
pass
class variable(object):
def __init__(self, va...
When to use setAttribute vs .attribute= in JavaScript?
...
This answer is not clear enough...I don't really feel I understand this yet.
– temporary_user_name
Oct 24 '13 at 21:48
1
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What is uint_fast32_t and why should it be used instead of the regular int and uint32_t?
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int may be as small as 16 bits on some platforms. It may not be sufficient for your application.
uint32_t is not guaranteed to exist. It's an optional typedef that the implementation must provide iff it has an unsigned integer type of exactl...
How do I get bash completion to work with aliases?
...d also add __git_complete g __git_main to get code completition working on all git commands.
– Ondrej Machulda
Apr 15 '13 at 12:03
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In which case do you use the JPA @JoinTable annotation?
... project_id
name name task_id
The Project_Tasks table is called a "Join Table". To implement this second solution in JPA you need to use the @JoinTable annotation. For example, in order to implement a uni-directional one-to-many association, we can define our entities as such:
Proj...
Iterate over model instance field names and values in template
...f that instance in table format, with the field name (verbose_name specifically if specified on the field) in the first column and the value of that field in the second column.
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How can a LEFT OUTER JOIN return more records than exist in the left table?
I have a very basic LEFT OUTER JOIN to return all results from the left table and some additional information from a much bigger table. The left table contains 4935 records yet when I LEFT OUTER JOIN it to an additional table the record count is significantly larger.
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