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let a = null; a ??= "default"; // a = "default" (only if null/undefined) let b = 0; b ||= 42; // b = 42 (assigns if falsy) let c = 1; c &&= c * 2; // c = 2 (assigns if truthy) // Equivalent verbose forms: a = a ?? "default"; b = b || 42; c = c && c * 2;
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