Re: [xml] FW: Regular expression evaluation

[Daniel Veillard <veillard redhat com>]

On Thu, Aug 09, 2007 at 08:11:37PM +0530, harbhanu wrote:
>    >  It could be errors in building the initial automata, it could be an
>    error
>
>    > when removing epsilon transitions, or it could be an error
>
>    > when doing the execution, likely one of the 2 first ones.
>
>
>    It is freeing the state node marked as the start state for the second
>
>    atom(01),  inside  function  xmlFAEliminateEpsilonTransitions,  inturn
>    invoked from xmlRegexpCompile.
>
>
>    regexp: '(2){0,1}1'
>
>    3 atoms:
>
>     00  atom: charval once char 2
>
>     01   atom:  subexpr  once start -572662307 end 2 <<< start pointer is
>    getting freed
>
>     02  atom: charval once char 1
>
>    6 states:
>
>     state: START 0, 4 transitions:
>
>      trans: removed
>
>      trans: removed
>
>      trans: count based 0, epsilon to 4
>
>      trans: counted 0, char 2 atom 0, to 2
>
>     state: NULL
>
>     state: 2, 3 transitions:
>
>      trans: count based 0, epsilon to 4
>
>      trans: removed
>
>      trans: counted 0, char 2 atom 0, to 2
>
>     state: NULL
>
>     state: 4, 1 transitions:
>
>      trans: char 1 atom 2, to 5
>
>     state: FINAL 5, 0 transitions:
>
>    1 counters:
>
>     0: min -1 max 0
>
>
>    I  am  not  sure  whether this node is deleted because of some problem
>    while creation of
>
>    the    automata   or   the   problem   entirely   lies   in   function
>    xmlFAEliminateEpsilonTransitions.
>
>
>    Is  the  regular  expression  created  correctly??  To  me  the  third
>    transition in state 2, should move to state 4...
>
>
>    Any clues to take it forward??

  Not really, I would basically have to draw the graphs and poke at the code
if I were to chase it now. maybe I will look at it tonight,

Daniel

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