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In a top-level, node.js console application, I have this:

var obj1 = { a: 1 };
var obj2 = { a: 2 };
var funcA = function () { return obj1.a + obj2.a };
var funcB = new Function("return obj1.a + obj2.a");
console.log(funcA()); // => 3
console.log(funcB()); // => ReferenceError: obj1 is not defined

Functions created by the Function constructor (funcB) are documented to "only be able to access their own local variables and global ones", but obj1 is global, and it cannot see it.

I need some way to get funcB to behave like funcA. It is ok to add code before the return, and/or add arguments to funcB, but I am trying to find a way that does not alter or require parsing the source after the return. I feel I need to understand why it can't even see the globals first.

Jeff Mercado
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jgg
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    To define a global var in Node, you have to explicitly say `global.obj1` & `global.obj2`. – 4castle Aug 11 '16 at 00:18
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    Then it seems a duplicate of [node.js global variables?](http://stackoverflow.com/q/5447771/1529630) – Oriol Aug 11 '16 at 00:24
  • Btw, using `new Function()` is typically a bad idea, for the same reasons as [not using `eval()`](http://stackoverflow.com/q/86513/5743988). – 4castle Aug 11 '16 at 00:31
  • @4castle most people who use the `Function` constructor know what they are doing – Bergi Aug 11 '16 at 00:49
  • @Bergi I can't say the same for those who browse SO though. – 4castle Aug 11 '16 at 00:55

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