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What does a lazy val do?
... printed when it's initialized in same way (I have taken x as var intentionally here - to explain when y gets initialized). Next when y is called, it's initialized as well as value of last 'x' is taken into consideration but not the old one.
Hope this helps.
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What is the purpose of Node.js module.exports and how do you use it?
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module.exports is the object that's actually returned as the result of a require call.
The exports variable is initially set to that same object (i.e. it's a shorthand "alias"), so in the module code you would usually write something like this:
let myFunc1 = func...
Create nice column output in python
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This will make all columns the same width, which is not what column -t does.
– intuited
Dec 5 '12 at 0:54
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How to concatenate columns in a Postgres SELECT?
...catenated to NULL is NULL. If NULL values can be involved and the result shall not be NULL, use concat_ws() to concatenate any number of values (Postgres 9.1 or later):
SELECT concat_ws(', ', a, b) AS ab FROM foo;
Or concat() if you don't need separators:
SELECT concat(a, b) AS ab FROM foo;
No...
How to display unique records from a has_many through relationship?
...ugh => :orders, :select => "DISTINCT products.*). In the first case, ALL records are fetched and rails removes the duplicates for you. In the later case, only non-duplicate records are fetched from the db so it might offer better performance if you have a large result set.
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C/C++ macro string concatenation
...rings you can just do:
#define STR3 STR1 STR2
The preprocessor automatically concatenates adjacent strings.
EDIT:
As noted below, it's not the preprocessor but the compiler that does the concatenation.
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How can I save an image to the camera roll?
...ng 4.3) and am not sure how to save an image to the device's camera roll. All that I have done so far is set up an IBAction for the button to save the image. What library method or function can I use to save an image to the user's camera roll?
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What are the most common non-BMP Unicode characters in actual use? [closed]
... ‹ › GC=Zs EM SPACE
528576 U+0003BC ‹μ› GC=Ll GREEK SMALL LETTER MU
519669 U+0003B2 ‹β› GC=Ll GREEK SMALL LETTER BETA
512312 U+0003B1 ‹α› GC=Ll GREEK SMALL LETTER ALPHA
491842 U+00200A ‹ › GC=Zs HAIR SPACE
462505 U+0000B0 ‹°› GC=So DE...
to remove first and last element in array
...moves the last element from an array and returns only that element.
See all methods for an Array.
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enum.values() - is an order of returned enums deterministic
...och is right about not relying on the ordinal and if the asker's example really involves enums like EN_TWO then he is relying on the ordinal and shouldn't do this. But to rely on the order is perfectly fine. In fact, as order is guaranteed, to create a field specifically for order would be writing r...