php_pipe_operator.php.md

function li( $str )
{
    return pipe( "<li> $str </li>" );
}

function h1( $str )
{
    return pipe( "<h1> $str </h1>" );
}

function pipe( $args )
{

    return function( $fun = NULL ) use( $args )
    {
        
        if( !is_callable ( $fun ) ) return $args;
        
        return call_user_func ( $fun, $args );
      
    };
}

echo pipe
     ( "Text argument" ) // This could be anything, scalar variable, array, object .. etc
     ( "li" )
     ( "h1" )
     ();

//OUTPUT
// <h1> <li> Text argument </li> </h1>