
What is the Return Value of typeof typeof 1?
Do you know, what is the return value of the following JavaScript expression?
typeof typeof 1
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If you've guessed it was "string", then you were right. Let's take it apart to see why is that. The code above can be rewritten as:
typeof (typeof 1)
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This can be broken down, further into two pieces:
typeof 1
typeof (<the return value of typeof 1>)
// This will return "number"
typeof 1
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The first part will return "number", and it's type is a string:
// This will return "string"
typeof "number"
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This means, that typeof typeof 1
will return "string".

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