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How to convert Nonetype to int or string?
...onditions under which it gives None and determine a sensible value to use for that, with the usual conditional code:
result = could_return_none(x)
if result is None:
result = DEFAULT_VALUE
...or even...
if x == THING_THAT_RESULTS_IN_NONE:
result = DEFAULT_VALUE
else:
result = could_...
Regex lookahead, lookbehind and atomic groups
...hese things in my regex body but I haven't got a clue what I can use them for.
Does somebody have examples so I can try to understand how they work?
...
NumPy or Pandas: Keeping array type as integer while having a NaN value
...e a preferred way to keep the data type of a numpy array fixed as int (or int64 or whatever), while still having an element inside listed as numpy.NaN ?
...
How to find the lowest common ancestor of two nodes in any binary tree?
...
Nick Johnson is correct that a an O(n) time complexity algorithm is the best you can do if you have no parent pointers.) For a simple recursive version of that algorithm see the code in Kinding's post which runs in O(n) time.
But keep in min...
Combine two ActiveRecord::Relation objects
...rst_name_relation.merge(last_name_relation)
If you want to combine using OR (union), use or†:
first_name_relation.or(last_name_relation)
† Only in ActiveRecord 5+; for 4.2 install the where-or backport.
share
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Generic method multiple (OR) type constraint
...
That is not possible. You can, however, define overloads for specific types:
public void test(string a, string arg);
public void test(string a, Exception arg);
If those are part of a generic class, they will be preferred over the generic version of the method.
...
How to install Android SDK Build Tools on the command line?
...s not include the build tools in the list. They're in the "obsolete" category. To see all available downloads, use
android list sdk --all
And then to get one of the packages in that list from the command line, use:
android update sdk -u -a -t <package no.>
Where -u stands for --no-ui,...
JavaScript checking for null vs. undefined and difference between == and ===
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How do I check a variable if it's null or undefined...
Is the variable null:
if (a === null)
// or
if (a == null) // but see note below
...but note the latter will also be true if a is undefined.
Is it undefined:
if (typeof a === "undefined")
// or
if (a ==...
How do you get the logical xor of two variables in Python?
How do you get the logical xor of two variables in Python?
24 Answers
24
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CSS media queries: max-width OR max-height
...SS media query, is there any way you can specify multiple conditions with "OR" logic?
3 Answers
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