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[REBOL] Re: Problem with parsing ISO-8859-1 encoded text

From: rotenca::telvia::it at: 30-Sep-2003 23:38

Changing the string while it is parsed is not an easy programming style. It is better to copy it in another location, it is almost always more fast. But if one wants to do it, he must keep in mind these rules: 1) get the next location and pass it back to parse 2) use opt for paren expressions Example: parse "12" [h: "12" opt (h: change/part h "3" 2) :h] ;==true instead, without opt: parse "12" [h: "12" (h: change/part h "3" 2) :h] ;==false There is at least one thread on this mailing list about this "feature". The point is that also paren are matched against the string only to see if the string is already at end, if the string is shorted by the paren rule, parse has nothing to match with and the paren rule makes parse to fail. --- Ciao Romano