       delete h.hdr; stream.match /[^⍝\n\r]*/; s = stream.current()
       if /^\s*:/.test(s) || dfnHeader.test s
         stream.backUp s.length
-      else if /^\s*$/.test s
-        delete h.vars
       else
         h.vars = s.split notName
       'apl-trad'

    else
      if /^\s*:(?:end|else|andif|orif|case|until)/i.test s then la.oi else la.ii

  fold: 'indent'

            "apl-dfn apl-dfn#{dd}"
          else if c == '∇'
            i = a.length - 1; while i && a[i].t != '∇' then i--
            if i then a.splice i; delete h.vars else a.push t: '∇', oi: n, ii: n + swm; h.hdr = 1
            'apl-trad'
          else if c == ':'
            ok = 0
            switch kw = stream.match(/\w*/)?[0]?.toLowerCase()
