comparison - (...()) vs. (...)() in javascript closures

Question

asked Oct 17, 2021 in Technique[技术] by 深蓝 (71.8m points)

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1 Answer

深蓝 · Answer 1 · 2021-10-16T22:22:54+0000

There's no difference. Both are valid ways to get the JavaScript parser to treat your function as an expression instead of a declaration.

Note that + and ! will also work, and are sometimes used by minifiers to save a character of size:

+function() {  
    var foo = 'bar';  
}();

!function() {  
    var foo = 'bar';  
}();

EDIT

As @copy points out, for completeness, ~ and - will also work.

-function() {  
    var foo = 'bar';  
}();

~function() {  
    var foo = 'bar';  
}();