JuniorTheoryCommon

What does the program print?

PHP

<?php

$bonus = 5;
$pay = fn(int $base) => $base + $bonus;
$bonus = 50;
$len = strlen(...);
echo $pay(100), ' ', $len('abcd'), "\n";

105 4

Expecting 150, as if fn read $bonus when called: an arrow function captures by value at creation, so $bonus = 50 later does not reach it.
Expecting an arrow function to need use, like an anonymous one: fn captures every outer variable its expression mentions, automatically.

JuniorTheoryCommon

PHP

<?php

$bonus = 5;
$pay = fn(int $base) => $base + $bonus;
$bonus = 50;
$len = strlen(...);
echo $pay(100), ' ', $len('abcd'), "\n";

105 4

Expecting 150, as if fn read $bonus when called: an arrow function captures by value at creation, so $bonus = 50 later does not reach it.
Expecting an arrow function to need use, like an anonymous one: fn captures every outer variable its expression mentions, automatically.