Function call optimization in V8

Question

Does V8 optimize multiple function calls that are the same function and arguments? In the example below Variance is called twice with the same arguments.

var Variance = require('variance');

function summary(items) {        
    return {
      variance: Variance(items.value.map((item) => item.value)),
      standardDeviation: Math.sqrt(Variance(items.value.map((item) => item.value))),
    };
}

Answer 1

v8确实优化了使用相同参数重复调用的函数，但是在您的示例中，它们实际上不是相同的参数（它们是不同的对象/数组引用）。