javascript - What is the order of precedence for boolean operators in JS? -

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 e.pagex = e.clientx + (html && html.scrollleft || body && body.scrollleft || 0) - (html.clientleft || 0)

how expression evaluate?

you can find precedence table javascript operators on mdn: https://developer.mozilla.org/en/javascript/reference/operators/operator_precedence. great source javascript documentation in general.

anyway, && has higher precedence || a && b || c || d equivalent (((a && b) || c) || d). similar many other language c-inspired syntax.


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