CODEWITHSUNDEEP
phpfunction
user3287266
user3287266

Reputation: 35

PHP: strange function call function()()

It may be a very strange question, but I need to be sure if it really exists or not. I've got the recruitment task for a PHP developer position with the following task:

Make a function to sum two numbers a and b but it must be called as sum(a)(b)

I've never seen anything like that and can't find anything about functions like the above. The recruiter says it's not a typo; I'm confused.

Upvotes: 3

Views: 88

Answers (1)

georg
georg

Reputation: 214949

This assignment expects you to understand partial application. Basically, your sum function should return a function that accepts one argument and takes the other one from the surrounding closure:

// Javascript
function sum(a) { return function(b) { return a + b  } }
sum(3)(4) // 7

You can do almost the same in php:

function sum($a) {
    return function($b) use($a) {
        return $a + $b;
    };
}

but since php doesn't allow two calls in a row, you'll need a temporary variable:

$add3 = sum(3);
print $add3(4); // 7

This

 sum(3)(4);

is not possible in php (as of 5.5) - parse error.

I'm pretty sure your interviewer actually means javascript, not php (note the lack of $'s in the assignment).

Upvotes: 10

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