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Why is it necessary to set the prototype constructor?
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Note: The constructor attribute does not have any special meaning in JS, so you might as well call it bananashake. The only difference is that the engine automatically initializes constructor on f.prototype whenever you declare a function f. However, it can be overwritten any time.
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What does the “Just” syntax mean in Haskell?
...s a type, Maybe a, which is parameterized by a type variable a, which just means that you can use it with any type in place of a.
Constructing and Destructing
The type has two constructors, Just a and Nothing. When a type has multiple constructors, it means that a value of the type must have been ...
SQL Server: Difference between PARTITION BY and GROUP BY
...on and the MAX amount across all sales regions in the same row.
This does mean you will have repeating data, but it may suit the end consumer in the sense that data has been aggregated but no data has been lost - as would be the case with GROUP BY.
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How to tell if browser/tab is active [duplicate]
...ment.hidden) {
// do what you need
}
This specification defines a means for site developers to
programmatically determine the current visibility state of the page in
order to develop power and CPU efficient web applications.
Learn more (2019 update)
All modern browsers are supportin...
Elements order in a “for (… in …)” loop
...ction stored in a property of an object is called a method.
I guess that means you cant rely on the properties being enumerated in a consistent order across JavaScript implementations. (It would be bad style anyway to rely on implementation-specific details of a language.)
If you want your order ...
View's SELECT contains a subquery in the FROM clause
...SQL 5.7.7, subqueries cannot be used in the FROM clause of a view.
This means, that choosing a MySQL v5.7.7 or newer or upgrading the existing MySQL instance to such a version, would remove this restriction on views completely.
However, if you have a current production MySQL version that is earl...
How do I create multiple submit buttons for the same form in Rails?
... edited Nov 18 '15 at 14:54
idmean
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answered Apr 22 '13 at 12:29
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Why an interface can not implement another interface?
What I mean is:
7 Answers
7
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Find files containing a given text
...-ir --include=*.{php,html,js} "(document.cookie|setcookie)" .
The r flag means to search recursively (search subdirectories). The i flag means case insensitive.
If you just want file names add the l (lowercase L) flag:
egrep -lir --include=*.{php,html,js} "(document.cookie|setcookie)" .
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Is there a float input type in HTML5?
...Code <= 57) ||
event.charCode == 46 || event.charCode == 0 ">
Meaning :
Char code :
48-57 equal to 0, 1, 2, 3, 4, 5, 6, 7, 8, 9
0 is Backspace(otherwise need refresh page on Firefox)
46 is dot
&& is AND , || is OR operator.
if you try float with comma :
<input type="te...