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Can modules have properties the same way that objects can?
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edited Mar 31 '19 at 9:48
mari.mts
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answered May 19 '09 at 1:09
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How do you use “
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function(x) x ^ exponent
}
square <- power(2)
square(2) # -> [1] 4
square(4) # -> [1] 16
cube <- power(3)
cube(2) # -> [1] 8
cube(4) # -> [1] 64
The ability to manage variables at two levels also makes it possible to maintain the state across function invocations by allowing...
How to determine device screen size category (small, normal, large, xlarge) using code?
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421
You can use the Configuration.screenLayout bitmask.
Example:
if ((getResources().getConfigur...
What's the best way of implementing a thread-safe Dictionary?
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43
As Peter said, you can encapsulate all of the thread safety inside the class. You will need to...
Sorting a Python list by two fields
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edited Sep 4 '15 at 8:54
BrechtDeMan
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How can I find all of the distinct file extensions in a folder hierarchy?
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– Ivan Nevostruev
Aug 20 '13 at 20:43
1
On Windows, this works better and is much faster than fi...
How to write an inline IF statement in JavaScript?
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Mr.Web
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answered Apr 22 '12 at 17:40
MattWMattW
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Primary key or Unique index?
...1 (foo, bar) VALUES (3, 1); -- OK
INSERT INTO table1 (foo, bar) VALUES (1, 4); -- Fails!
Duplicate entry '1' for key 'ux_table1_foo'
The last insert fails because it violates the unique index on column foo when it tries to insert the value 1 into this column for a second time.
In MySQL a unique ...
How to remove duplicate values from a multi-dimensional array in PHP
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647
Here is another way. No intermediate variables are saved.
We used this to de-duplicate result...
PHP Sort a multidimensional array by element containing date
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answered May 26 '10 at 6:44
Ferdinand BeyerFerdinand Beyer
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