func create(_data)
  fvar(old)
  old = block.select(BLK_HEAD)
  println('function reg_callback' + code(_id_) + '($matches) {')
  block.inclvl()
  include("func_head")  
    event(onFindMatch, '$matches')
  include("func_tail")  
  block.declvl()
  println('}')
  block.select(old)
  
  return('preg_replace_callback(' && Pattern && ', "reg_callback' + code(_id_) && '", ' && Text && ')')
end

func doReplace(_data)
  fvar(s)
  s = create(_data)
  if(linked(Result))
    println(pr_rep, ' = ', s, ';')
    event(onReplace, pr_rep)
  else
    if(linked(onReplace))
      event(onReplace, s)
    else 
      println(s, ';')
    end
  end
end

func Result(_data)
  if(linked(doReplace))
    return(pr_rep)
  else
    return(create(_data))
  end
end