How does the JavaScript instanceOf method execute in this statement?

Question

var a = "words";
a instanceOf String;    
#=> false

I can't understand how this code snippet works.

Is instanceof a method of a, or of this which locates it in the default scope?
If String here is a parameter passed to instanceof, how come it doesn't have parentheses?

James M · Accepted Answer · 2012-01-31 13:34:32Z

4

instanceof is an operator, so it's more like + than a function.

answered Jan 31, 2012 at 13:34

James M

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2 Comments

It makes sense, but to be frank, this operator really strange to me

is a is not a a instance of String, what kind of instance it is, and how to use command to check it, something like a.class in Ruby

Quentin · Accepted Answer · 2012-01-31 13:34:20Z

1

answered Jan 31, 2012 at 13:34

Quentin

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