Matching with variables

Originally published on php2rust.dev — part of the PHP to Rust course. View this lesson on the original site.

Patterns can bind matched values to variables. In Rust, use variable names in patterns; match guards add extra conditions. PHP match returns values but does not destructure or bind like Rust.

Rust

fn main() {
    let pair = (2, -2);
    match pair {
        (x, y) if x == y => println!("Equal"),
        (x, y) if x + y == 0 => println!("Opposites"),
        (x, y) => println!("Different: ({}, {})", x, y),
    }
}

PHP

<?php
$pair = [2, -2];
[$x, $y] = $pair;
if ($x === $y) {
    echo "Equal\n";
} elseif ($x + $y === 0) {
    echo "Opposites\n";
} else {
    echo "Different: ($x, $y)\n";
}

Comparison

• Rust: Patterns bind variables; if guards add conditions; destructuring in the pattern.
• PHP: Destructuring via [$a, $b] = $arr; conditions in if/elseif.
• Rust: Variable binding is part of the pattern; guards use if after the pattern.
• PHP: No pattern binding in match; use separate destructuring and conditionals.

References

• Rust: Destructuring
• PHP: List

What's next

Next: Combining patterns.

From PHP to Rust — Rust Syntax and Functions