indent.php.peg

toplevel = ys:element
         (eol y:element -> { $ys = array_merge($ys, $y); } )*
         -> $ys

block = ys:element
        (eol samedent y:element -> { $ys = array_merge($ys, $y); } )*
        -> $ys

element = n:name ":" spaces? eol indent b:block -> {
              array_pop($this->indent);
              return array($n => $b);
          }
        / n:name ":" spaces? v:value -> array($n => $v)

samedent = s:spaces ?$s === implode("", $this->indent)

indent = s:spaces ?{
             $prev = implode("", $this->indent);
             if (strncmp($prev, $s, $l = strlen($prev)) === 0) {
                 array_push($this->indent, substr($s, $l));
                 return TRUE;
             }
             return FALSE;
         }

eol = "\r\n" / "\n" / "\r"

spaces = [ \t]+

name = [a-zA-Z][a-zA-Z0-9_-]*

value = (!eol .)*