javascript - Are these statements functionally equivalent? -

javascript - Are these statements functionally equivalent? -

as far can tell function same, wanted create sure. utilize latter statement less code , seems more efficient.

function updaterunningtotals(taxexempt, disctype, discamt){ if (typeof taxexempt === 'undefined') { taxexempt = false; } taxexempt = taxexempt || false; }

i have been using if, have seen latter statement in open source projects. same thing? performance benefit?

edit: taxexempt, in scenario may not passed in.

> if (typeof taxexempt === 'undefined') { taxexempt = false; }

in case, textexempt set false if value undefined.

> taxexempt = taxexempt || false;

in case, taxexempt set false if value coerces false (i.e. toboolean(taxexempt) returns false), e.g. might null, 0, false, nan, '' or undefined.

so no, not functionally equivalent. , choosing sec because it's less code not sound logic. first clearer logic most.

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