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demystify Flask app.secret_key
If app.secret_key isn't set, Flask will not allow you to set or access the session dictionary.
2 Answers
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Deleting Objects in JavaScript
...a C++ delete. (And accessing one of them would cause a crash. To make them all turn null would mean having extra work when deleting or extra memory for each object.)
Since Javascript is garbage collected, you don't need to delete objects themselves - they will be removed when there is no way to ref...
Extract elements of list at odd positions
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Solution
Yes, you can:
l = L[1::2]
And this is all. The result will contain the elements placed on the following positions (0-based, so first element is at position 0, second at 1 etc.):
1, 3, 5
so the result (actual numbers) will be:
2, 4, 6
Explanation
The [1::2]...
Structs in Javascript
...a retyping is still an issue, as there are more jumps than copying the new ___ ( , , , ) archetype. Also, there is no readability. Once you get used to coding, new READABLE_PART(ignore everything in here) becomes very scannable and self documenting, as opposed to {read: "ignore", everything: "igno...
Unique ways to use the Null Coalescing operator [closed]
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Well, first of all, it's much easier to chain than the standard ternary:
string anybody = parm1 ?? localDefault ?? globalDefault;
vs.
string anyboby = (parm1 != null) ? parm1
: ((localDefault != null) ? localDefault
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How to handle click event in Button Column in Datagridview?
... a single button per grid, you can jump right off to the races.
Putting it all together:
C#:
private void dataGridView1_CellContentClick(object sender, DataGridViewCellEventArgs e)
{
var senderGrid = (DataGridView)sender;
if (senderGrid.Columns[e.ColumnIndex] is DataGridViewButtonColumn &am...
How to access data/data folder in Android device?
...'backup my data'. The resulting 'backup.ab' file on your computer contains all application data in android backup format. Basically it's a compressed tar file. This page explains how you can use OpenSSL's zlib command to uncompress it.
You can use the adb restore backup.db command to restore the b...
What's the fastest algorithm for sorting a linked list?
...; there are no pathological cases.
Auxiliary storage requirement is small and constant (i.e. a few variables within the sorting routine). Thanks to the inherently different behaviour of linked lists from arrays, this Mergesort implementation avoids the O(N) auxiliary storage cost normally assoc...
Resolving ambiguous overload on function pointer and std::function for a lambda using +
...in comp.lang.c++.moderated if a closure type could add a typedef for result_type and the other typedefs required to make them adaptable (for instance by std::not1). I was told that it could not because this was observable. I'll try to find the link.
– Cassio Neri
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Is C++14 adding new keywords to C++?
...last change to the keywords table took place back in August 2011 (it's actually the first commit: that table hasn't changed since the repo went live around the time C++11 was being finalised).
Alternatively we can ask GitHub to compare the two drafts that were sent for ballot for both versions of ...