28 lines
1.1 KiB
Markdown
28 lines
1.1 KiB
Markdown
---
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tags:
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- backend
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- node-js
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---
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# Global object
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> In Node every function and variable should be scoped to a module. We should
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> not define functions and variables within the global scope.
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- In Node the equivalent to the browser's `Window` object is `global`. The
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properties and methods that belong to this method are available anywhere in a
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program.
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- Just as we can technically write `Window.console.log()`, we can write
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`global.console.log()` however in both cases it is more sane to use the
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shorthand.
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- However if we declare a variable in this scope in browser-based JavaScript,
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this variable becomes accessible via the `Window` object and thus is
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accessible in global scope. The same is not true for Node. If you declare a
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variable at this level it will return undefined.
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- This is because of Node's modular nature. If you were to define a function
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`foo` in a module and then also define it in the global scope, when you call
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`foo`, the Node interpreter would not know which function to call. Hence it
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chooses not to recognise the global `foo`, returning undefined.
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