What are the ways to simulate python pointers given that Python does not have traditional pointers like in languages such as PHP or C++? For example, in the following Python code:
a = 1
b = a # How can we modify this line so that b "points to" a?
a = 2
print(b)
We would expect b to reflect the updated value of a after a is changed. However, as it stands, b remains unchanged, outputting 1. How can we modify the behavior so that b will show 2 after a is updated?
This is similar to how we can achieve reference-based behavior in PHP:
<?php
class Form {
public $data = [];
public $fields;
function __construct($fields) {
$this->fields = $fields;
foreach($this->fields as &$field) {
$this->data[$field['id']] = &$field['value'];
}
}
}
$f = new Form([
[
'id' => 'fname',
'value' => 'George'
],
[
'id' => 'lname',
'value' => 'Lucas'
]
]);
echo $f->data['fname'], $f->fields[0]['value']; // Outputs: George George
$f->data['fname'] = 'Ralph';
echo $f->data['fname'], $f->fields[0]['value']; // Outputs: Ralph Ralph
Similarly, in C++, pointers are explicitly used for reference manipulation:
#include <iostream>
using namespace std;
int main() {
int a;
int* b = &a;
a = 1;
cout << a << endl << *b << endl; // Outputs: 1 1
return 0;
}
In these cases, references or pointers allow one variable to reflect changes made to another. How can we achieve a similar effect in Python using Python pointers or reference behavior?