I have some code that looks like
self = @
and then later on it's using @someMethodName or self.someMethodName
Does @ have some special meaning?
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shaedrich
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Noah Clark
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Is that symbol existed in jquery? – Eli Jan 03 '13 at 16:38
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sooo..... is it a Javascript file or a coffeescript file? – SDC Jan 03 '13 at 16:39
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@SDC it's a coffeescript file, but presumably you could use that if Javascript had defined it. – Noah Clark Jan 03 '13 at 16:41
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See http://stackoverflow.com/a/9337047/717267 – Eduardo Cuomo Apr 11 '17 at 18:00
3 Answers
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@ is not a valid character for a javascript identifier. Identifiers may only contain $, _, digits and letters.
In coffeescript, @ means this.
CoffeeScript has a few nice features related to the this keyword. First, CoffeeScript uses the @ symbol as shorthand for this.. For example, @foo is equivalent to this.foo. Second, if you use the @ symbol in the parameters of a function, CoffeeScript will automatically assign those values as properties of the object.
Edit: As far as jQuery is concerned, the same identifier rules as javascript apply since jQuery is just javascript. For other uses of @ in jQuery, see this question or the docs.
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14It's worth adding that `@foo` means `this.foo` in CoffeeScript. – Trevor Burnham Jan 03 '13 at 18:47
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It may also be worth noting that `=>` is pretty freaking confusing when you're trying to read someone else's CoffeeScript, imho. – cwharris Jan 03 '13 at 19:42
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@ is shortcut for this in coffeescript
So
self = @
is coffeescript for:
var self = this;
Esailija
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Since the design of CoffeeScript a couple of years have passed and not everything which was proposed in CoffeeScript made it into ECMA script. Instead of being used as a shortcut for this, it's proposed to be used for decorators.
shaedrich
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