c++和js中参数入栈顺序区别

一.原来一直c++开发,偶尔会遇到参数入栈顺序的问题,而c++是右侧函数先入栈.例子如下:

#include <iostream>using namespace std;int left(int& a){    a *= 2;    cout << "left " << a << endl;     return a;  //10}int right( int& a){    a += 2;    cout << "right " << a << endl;    return a; //5}int _plus( int a = 0, int b = 0 ){    cout << "_plus " << a << " " << b << endl;    return a + b; //15}int main(){    int a = 3;    cout << _plus( left(a), right(a) ) << endl; //15    int b;    cin >> b;}

输出结果:
right 5
left 10
15

c++的入栈顺序先right后left,所以先加后乘,结果为15.

二.由于先入为主,在后来学习js的时候,也遇到同样的问题结果入栈书序顺序为先成左后右而且全程是引用

function test7(){function left(a){a *= 2;console.log( "left()", a);return a;}function right(a) {a += 2;console.log( "right()", a);return a;}function _plus( a = 0, b = 0 ){console.log( "_plus a:" + a + " b:" + b );return a + b;}var a = 3;console.log( _plus( left(a), right(a) ) );}test7();

输出结果:

left() 6
right() 5
_plus a:6 b:5
11

js中参数先左后右,结果与c++不同.而且默认是引用传值,所以更应该小心.