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I have a class in a seperate file. I need to create an instance of it in another file. I tried this:

var connection = new require('./connection.js')("ef66143e996d");

But this is not working as I wanted. Right now I am using this as a temporary solution: 

var Connection = require('./connection.js'); 
connection = new Connection("ef66143e996d");

Two Questions;

First, why doesn't that work.
Second, how can I accomplish this with a one-liner?

DifferentPseudonym
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1 Answers1

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The new keyword applies itself on the first function it comes across. In this case, that happens to be require. Wrapping the statement in parentheses will expose the correct function:

var connection = new (require('./connection.js'))("ef66143e996d");
jperezov
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    This works, ok. But I invoked the `require` with `("ef66143e996d")`. Why doesn't `new` apply to the function returned from `require('./connection.js')("ef66143e996d")`. This must be the first function it comes across. – DifferentPseudonym Nov 19 '15 at 18:21
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    When running `new require('connection')()`, require is the first function it comes across. It's being evaluated left-to-right. Wrapping `require('connection')` in parentheses makes it so that whatever the parentheses resolves to is what `new` is being applied to. – jperezov Nov 19 '15 at 18:41
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    To clarify, assuming `require('./connection.js')` exposes the function `Connection`, the `Connection` function _isn't_ exposed until the `require` function is invoked. The `new` keyword would trigger before the `require` function _unless_ the function is wrapped in parentheses. It is the same reason `3 * 2 + 1 = 7`, but `3 * (2 + 1) = 9`. Think of the `new` keyword as the multiplication in this example--it has a higher precedence. – jperezov Nov 19 '15 at 18:49
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    Thanks a lot for your explanation, you made things clearer in mind. – DifferentPseudonym Nov 19 '15 at 19:07