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Get all non-unique values (i.e.: duplicate/more than one occurrence) in an array
... do this? I just need to find what the duplicated values are - I don't actually need their indexes or how many times they are duplicated.
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Finding duplicate values in MySQL
I have a table with a varchar column, and I would like to find all the records that have duplicate values in this column. What is the best query I can use to find the duplicates?
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Changing Vim indentation behavior by file type
...h a width of 2 characters for indenting (the noexpandtab option is set globally elsewhere in my configuration).
This is described here: http://vimdoc.sourceforge.net/htmldoc/usr_05.html#05.4, scroll down to the section on filetype plugins.
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AttributeError: 'module' object has no attribute
...ave mutual top-level imports, which is almost always a bad idea.
If you really must have mutual imports in Python, the way to do it is to import them within a function:
# In b.py:
def cause_a_to_do_something():
import a
a.do_something()
Now a.py can safely do import b without causing pro...
Reference assignment operator in PHP, =&
...rror changes made to another, instead of copying the existing data.
It's called assignment by reference, which, to quote the manual, "means that both variables end up pointing at the same data, and nothing is copied anywhere".
The only thing that is deprecated with =& is "assigning the result ...
Difference between
...ts, what type of object could you add to List foo3 that would be legal for all the above possible ArrayList assignments:
You can't add an Integer because foo3 could be pointing at a List<Double>.
You can't add a Double because foo3 could be pointing at a List<Integer>.
You can't add a ...
Python: Check if one dictionary is a subset of another larger dictionary
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Convert to item pairs and check for containment.
all(item in superset.items() for item in subset.items())
Optimization is left as an exercise for the reader.
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What does {0} mean when initializing an object?
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What's happening here is called aggregate initialization. Here is the (abbreviated) definition of an aggregate from section 8.5.1 of the ISO spec:
An aggregate is an array or a class with no user-declared constructors, no private or protected non...
The new syntax “= default” in C++11
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A defaulted default constructor is specifically defined as being the same as a user-defined default constructor with no initialization list and an empty compound statement.
§12.1/6 [class.ctor] A default constructor that is defaulted and not defined as deleted is im...
Awaiting multiple Tasks with different results
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After you use WhenAll, you can pull the results out individually with await:
var catTask = FeedCat();
var houseTask = SellHouse();
var carTask = BuyCar();
await Task.WhenAll(catTask, houseTask, carTask);
var cat = await catTask;
var house =...