zEn4X

zen4x.js

function zen4x(zc){
  var word = /[-\w$]+/, char = /^[^]/, digits = /\d+/;
  var kv = /([-\w$]+)(?:=([^\]]*))?\]?/, content = /{([^\}]*)}?/;
  var zs = zc.trim().split(/\s{0,}([>+])\s{0,}/);
  var root = <_/>, curs = [root], sep;
  for(let i = -1, l = zs.length; ++i < l; sep = zs[++i]){
    let [name] = word(zs[i]) || '';
    if(!name) continue;
    let lm = <{name}/>, n = 1;
    for(let _, m; char.test(_ = RegExp.rightContext);) switch(_[0]){
      case '#': lm.@id = word(_) || '';
      break;
      case '.': lm.@class += (lm.@class +'' && ' ') + (word(_) || '');
      break;
      case '[': if((m = kv(_))) lm['@'+ m[1]] = m[2] || '';
      break;
      case '{': if((m = content(_))) lm.appendChild(m[1]);
      break;
      case '*': n *= +digits(_) || 1;
    }
    let _curs = [], p = sep === '+';
    let sl = n > 1 && ~zc.indexOf('$') && lm.toXMLString();
    for each(let cur in curs){
      if(p) cur = cur.parent() || cur;
      for(let i = 1; i <= n; ++i){
        let clm = sl ? XML(sl.replace(/\$/g, i)) : lm.copy();
        cur.appendChild(clm);
        _curs.push(clm);
      }
    }
    curs = _curs;
  }
  return root.*;
}
// var pr = this.dump || this.print || this.alert;
// pr(zen4x('dl#id.cla.ss > dt{content} + dd > input[type=radio][name=$]*2'));