<?php
class Pipeline
{
    public static function make_pipeline(...$funcs)
    {
        return function($arg) use ($funcs)
        {
            foreach($funcs as $func){
                $arg = $func($arg);
            }
            return $arg;
        };
    }
}

$fun = Pipeline::make_pipeline(function($x) {
            return $x * 3;
        }, function($x) {
            return $x + 1;
        }, function($x) {
            return $x / 2;
       });
echo $fun(3); # should print 5