What would be the explanation for the strange javascript expression? -


in javascript following line of code gives answer 1

+ ! {} [true]

i couldn't understand how?

any gurus explanation appreciated.

{} empty object.

so {}[0] or {}[true] or {}[1] etc.. undefined

adding ! casts {}[0] boolean, returning opposite. (undefined becoming false, therefore returns true).

adding + casts int, true becomes 1.


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