When exporting a module that has another dependency, is it best to include that dependency within the module export function or outside of it? I usually see the latter, but it seems like it would be best to keep it in the local scope.
For example:
var foo = require('foo');
module.exports = function(d) {
return foo(d)/2;
}
vs.
module.exports = function(d) {
var foo = require('foo');
return foo(d)/2;
}
Only things exposed on module.exports and global can be accessed from other modules in node. Unlike in the browser, var creates a local reference. To quote from node's documentation:
In browsers, the top-level scope is the global scope. That means that in browsers if you're in the global scope var something will define a global variable. In Node this is different. The top-level scope is not the global scope;
var somethinginside a Node module will be local to that module.
The difference between the two versions is therefore minimal - the first incurs a lookup in the local scope, while the other hits require.cache every time the function is invoked. From what I have seen of node code, the former (var someVar = require('something');) seems to be preferred.
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