Does isMustBePresent get wrong value assigned?

[schnef]

While parsing matches, the isMustBePresent gets a new value assigned using an XOR AllOfExpression.java line 105 . This will however reset the variable to being not critical if the variable was set to critical previously and a new match has the MustBePresent flag set. Should an OR operation be used instead of an XOR?

// update mustBePresent state of the variable: if it is set before in the expression.
intervals.get(varId).isMustBePresent = intervals.get(varId).isMustBePresent ^ isMustBePresent;


[canhnt]

Because a Match with mustBePresent=true, it may return Indeterminate when attribute is missing.
And according to evaluating AllOf:

No “False” and at least one “Indeterminate” -> “Indeterminate”

Using Or reflects that rule: e.g. if there are two Indeterminate Matches, it returns Indeterminate.

[schnef]

So, we agree on the fact the XOR should be replaced by an OR?

[canhnt]

Thanks for your contribution. Actually this project was not active anymore. You can freely fork and improve.

PS: I might think about rewritten the engine using Go language with the updated algorithms in my last paper.