Re: Evaluate complex conditions

[edfishel@xxxxxxxxxx]

Terry,

The way I have done this in the past is to create a stack machine. Then to
evaluate a statement like (a = b and ( c = d or e = f)) you would read the
statement and create a stack program. Then use the stack machine to run the
stack program for each record to be queried.

>Terry Grider wrote:
>
>Sorry guys,  I didn't do a very good job of explaining what I was looking
for.
>I don't mean I want code that is an example of testing for complex
conditions, I
>mean I'm looking for code that will evaluate statements like the one in my
>original example and determine the truth of the statement.  You see, I'm
writing
>a query tool and I want the user to be able to provide selection criteria
in an
>english style IF format similar to cobol or other query tools I've seen.
I can
>currently handle simple criteria with "and/or" connectors, but I can't
seem to
>come up with a good method for handling multiple levels of parenthesis.
>
>> Has anyone ever written or seen an example of program code designed to
>> evaluate complex conditions?  For example, if you wanted to evaluate a =
>> b and (c = d or c = e or c = f).  I'm looking for something that can do
>> multiple levels of parenthesis and all "and/or" combinations.

Ed Fishel,
edfishel@US.IBM.COM      >


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