Ed Staub's questions

例如：

function makeFunc(a,b,c,d,e) {
    return () => {
        if (a) { /* do something expensive not referencing b,c,d,e */ }
        if (b) { /* do something expensive not referencing a,c,d,e */ }
        if (c) { /* do something expensive not referencing a,b,d,e */ }
        if (d) { /* do something expensive not referencing a,b,c,e */ }
        if (e) { /* do something expensive not referencing a,b,c,d */ }
    }
}

const func = makeFunc(true, false, false, false, false)
for ( let i=0; i < 100_000; i++) func()

我希望，在这个例子中，V8 能够优化if (x)闭包上的测试，只发出

/* do something expensive not referencing b,c,d,e */

if (a)执行100,000次之后。