Registriert seit: 30. Nov 2005
Ort: München
5.768 Beiträge
Delphi 10.4 Sydney
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Re: In Set or Not in Set? Frage zu Set.
6. Okt 2006, 15:44
Code:
The following operators take sets as operands.
Operator Operation Operand types Result type Example
+ union set set Set1 + Set2
– difference set set S - T
* intersection set set S * T
<= subset set Boolean Q <= MySet
>= superset set Boolean S1 >= S2
= equality set Boolean S2 = MySet
<> inequality set Boolean MySet <> S1
in membership ordinal, set Boolean A in Set1
The following rules apply to +, –, and *.
An ordinal O is in X + Y if and only if O is in X or Y (or both). O is in X – Y if and only if O is in X but not in Y. O is in X * Y if and only if O is in both X and Y.
The result of a +, –, or * operation is of the type set of A..B, where A is the smallest ordinal value in the result set and B is the largest.
The following rules apply to <=, >=, =, <>, and in.
X <= Y is True just in case every member of X is a member of Y; Z >= W is equivalent to W <= Z. U = V is True just in case U and V contain exactly the same members; otherwise, U <> V is True.
For an ordinal O and a set S, O in S is True just in case O is a member of S.
wobei Intersection = Schnittmenge ist.
Grüße
Klaus
Klaus
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