[PHP知识库]几大语言对列表添加字典时的深拷贝浅拷贝问题

dict = {}
list = []
for i in range(1,5):
    dict['id'] = i
    list.append(dict)

for v in list:
    print(v)

let arr = [];
let obj = {};
for (let i = 0; i < 5 ; i++) {
    obj['id'] = i;
    arr.push(obj);
}
console.table(arr);

<?php
$arr = [];
$obj = [];
for ($i = 0; $i < 5 ; $i++) {
    $obj['id'] = $i;
    $arr[]=$obj;
}
var_dump($arr);

package main

import "fmt"
import "container/list"

func main() {
	list := list.New()
	// var list list.List
	
	for i := 1; i <= 5; i++  { 
		obj := make(map[string]int, 5)
		obj["id"] = i
		list.PushBack(obj)
	}
	for v := list.Front(); v != nil; v = v.Next() {
		fmt.Println(v.Value)
	}
}

import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.HashMap;

class Test {
    public static void main(String[] args) {
        List<Object> list = new ArrayList<>();
        for (int i = 0; i < 5; i++) {
            Map<String, Object> map = new HashMap<>();
            map.put("id", i);
            list.add(map);
        }

        for (Object v : list) {
            System.out.println(v);
        }
    }
}

除了php 都是赋值地址到列表里面的(引用传递)
php因为使用了数组作为字典,它的数组是值赋值的,不是引用传递