How about this (example used is "(A AND B) OR (C OR D NOT E) OR Q"):

  1. Break the statement into smaller ones on the joiner -- AND, OR, NOT -- which are not inside parent expression. That will yield: { OR <-- { (A AND B) , (C OR D NOT E) } , OR <-- { Q } }.
  2. Go thru to each of the component of the broken down tokens, to search for the joiner as above, giving: { AND <-- { A, B } , OR <-- { C , D , NOT E } }.
  3. Do the above for all other sub components, till all are exhausted.
  4. Ending up w/... 
    { OR <-- 
    { AND <-- { A , B }
    , OR  <-- 
       { C , D
       , NOT <-- { E }
       }
     }
, OR  <-- { Q }
}

    [download]
  5. Last step would be add the appropriate signs (or nothing at all) based on parent joiner, which can be easily done in a loop.

Well, that is what currently comes to mind, bugs expected.

Updated (Jun 24 2003) the parsed expressions as after adding "OR Q" in the example, forgot to correctly update the hierarchy.

In reply to Re: converting a boolean syntax by parv
in thread converting a boolean syntax by glwtta

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