Router idea

lambda_router.php

<?php

class R {
    protected $matchers = [];
    function __invoke(...$matchers) {
        $uniq = uniqid();
        $this->matchers[$uniq] = $matchers;
        return $uniq;
    }
    
    function match($req) {
        $resolver = function($args, $matcher) use($req) {
            if (($match = $matcher($req)) !== false) {
                return ($args ?: []) + (is_array($match) ? $match : []);
            }
            return false;
        };
        foreach ($this->matchers as $name => $matchers) {
            if (($match = array_reduce($matchers, $resolver, false)) !== false) {
                return [$name, $match];
            }
        }
        return false;
    }
}

function m($m) {
    return function($req) use($m) {
        return $req['method'] === $m;
    };
}

$r = new R;
$m = [$r(m('GET')) => function($a) { return "Hello"; }];

list($n, $a) = $r->match(['method' => 'GET', 'path' => '/']);
var_dump($m[$n]($a));