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Accessing class variables from a list comprehension in the class definition
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Class scope and list, set or dictionary comprehensions, as well as generator expressions do not mix.
The why; or, the official word on this
In Python 3, list comprehensions were given a proper scope (local namespace) of their own, to p...
What is an existential type?
... type parameter. Second, invert control (this effectively swaps the "you" and "I" part in the definitions above, which is the primary difference between existentials and universals).
// A wrapper that hides the type parameter 'B'
interface VMWrapper {
void unwrap(VMHandler handler);
}
// A cal...
Correct way to use StringBuilder in SQL
...I think you've misquoted it, though; surely there aren't quotes around id2 and table?)
Note that the aim (usually) is to reduce memory churn rather than total memory used, to make life a bit easier on the garbage collector.
Will that take memory equal to using String like below?
No, it'll cau...
Find object in list that has attribute equal to some value (that meets any condition)
... None)
This gets the first item from the list that matches the condition, and returns None if no item matches. It's my preferred single-expression form.
However,
for x in test_list:
if x.value == value:
print("i found it!")
break
The naive loop-break version, is perfectly Pytho...
What is a lambda (function)?
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Lambda comes from the Lambda Calculus and refers to anonymous functions in programming.
Why is this cool? It allows you to write quick throw away functions without naming them. It also provides a nice way to write closures. With that power you can do things like...
What's the fundamental difference between MFC and ATL?
... nothing fancy), what is the fundamental difference I will see between ATL and MFC, to help me figure out which one to use?
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How to detect a Christmas Tree? [closed]
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I have an approach which I think is interesting and a bit different from the rest. The main difference in my approach, compared to some of the others, is in how the image segmentation step is performed--I used the DBSCAN clustering algorithm from Python's scikit-learn; it...
How to use filter, map, and reduce in Python 3
filter , map , and reduce work perfectly in Python 2. Here is an example:
7 Answers
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Object comparison in JavaScript [duplicate]
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Unfortunately there is no perfect way, unless you use _proto_ recursively and access all non-enumerable properties, but this works in Firefox only.
So the best I can do is to guess usage scenarios.
1) Fast and limited.
Works when you have simple JSON-style objects without methods and DOM nodes...
GridLayout and Row/Column Span Woe
The Android Developers Blog post introducing GridLayout shows this diagram of how spans impact automatic index allocation:
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