Why does Node not read the env var of the current shell? [duplicate]

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• What does “export” do in shell programming? 4 answers

As you can see below, I set an environment variable FOO, but when I execute console.log on the next line, it's undefined. If I set it on the same line where I execture console.log, it is present. Why is the behaviour as such?

$ FOO="123"
$ echo $FOO
123
$ node -e "console.log(process.env.FOO)"
undefined
$ FOO="123" node -e "console.log(process.env.FOO)"
123

Node version: 6.6.0

via Yang Shun