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Function in JavaScript that can be called only once
...
If by "won't be executed" you mean "will do nothing when called more than once", you can create a closure:
var something = (function() {
var executed = false;
return function() {
if (!executed) {
executed = true;
// do something
}
...
Create a temporary table in a SELECT statement without a separate CREATE TABLE
...RARY table is visible only to the current session, and is dropped automatically when the session is closed. This means that two different sessions can use the same temporary table name without conflicting with each other or with an existing non-TEMPORARY table of the same name. (The existing table i...
ObservableCollection Doesn't support AddRange method, so I get notified for each item added, besides
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Scott Dorman is correct. Calling the built-in Add method will trigger something like 3 events per add (a NotifyPropertyChange for item count, NotifyPropertyChange for item indexing[] and an NotifyCollectionChanged event for the item added). To get the...
What is __gxx_personality_v0 for?
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Martin v. LöwisMartin v. Löwis
110k1616 gold badges180180 silver badges226226 bronze badges
a...
What is the difference between String.Empty and “” (empty string)?
...ich makes string.Empty more efficient.
In version 2.0 and later of .NET, all occurrences of "" refer to the same string literal, which means "" is equivalent to .Empty, but still not as fast as .Length == 0.
.Length == 0 is the fastest option, but .Empty makes for slightly cleaner code.
See the ...
What does -> mean in Python function definitions?
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KatrielKatriel
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What's the common practice for enums in Python? [duplicate]
...nt, Matte = range(5)
– zekel
Dec 9 '10 at 2:12
81
Kinda late, but you can also do Shaded, Shiny, ...
In Python, if I return inside a “with” block, will the file still close?
...owLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by \u003ca href=\"https://imgur.com/\"\u003e\u003csvg class=\"svg-icon\...
How to update a record using sequelize for node?
...gt;
handleError(err)
)
Update 2016-03-09
The latest version actually doesn't use success and error anymore but instead uses then-able promises.
So the upper code will look as follows:
Project.update(
{ title: 'a very different title now' },
{ where: { _id: 1 } }
)
.then(result =&g...
What is dynamic programming? [closed]
...ith dynamic programming, you store your results in some sort of table generally. When you need the answer to a problem, you reference the table and see if you already know what it is. If not, you use the data in your table to give yourself a stepping stone towards the answer.
The Cormen Algorithms ...