Dawid Wysakowicz created FLINK-9576:

             Summary: Wrong contiguity documentation
                 Key: FLINK-9576
                 URL: https://issues.apache.org/jira/browse/FLINK-9576
             Project: Flink
          Issue Type: Bug
          Components: CEP, Documentation
            Reporter: Dawid Wysakowicz

Example for the contiguity is first of all wrong, and second of all misleading:

To illustrate the above with an example, a pattern sequence "a+ b" (one or more 
"a"’s followed by a "b") with input "a1", "c", "a2", "b" will have the 
following results:
Strict Contiguity: {a2 b} – the "c" after "a1" causes "a1" to be discarded.
Relaxed Contiguity: {a1 b} and {a1 a2 b} – "c" is ignored.
Non-Deterministic Relaxed Contiguity: {a1 b}, {a2 b}, and {a1 a2 b}.
For looping patterns (e.g. oneOrMore() and times()) the default is relaxed 
contiguity. If you want strict contiguity, you have to explicitly specify it by 
using the consecutive() call, and if you want non-deterministic relaxed 
contiguity you can use the allowCombinations() call.

Results for the relaxed contiguity are wrong plus they do not clearly explains 
the internal contiguity of kleene closure.

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