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Tuple Expression

< expression-1, ...expression-n >

A tuple expression represents the value of a member in a set of tuples. Each scalar subexpression inside the angle brackets represents the value of a tuple element. This form is used only with IN, SETOF, and set constructor expressions.

The following code demonstrates the tuple expression:

    proc optmodel;
       put (<1,2,3> in setof{i in 1..2}<i,i+1,i+2>);
       put ({<1,'a'>, <2,'b'>} cross {<3,'c'>, <4,'d'>});
 

The first PUT statement checks whether the tuple <1, 2, 3> is a member of a set of tuples. The second PUT statement outputs the cross product of two sets of tuples constructed by the set constructor.

This code produces the output in Output 6.34.

                                                                                
                                                                                 
                                                                                 
 1                                                                               
 {<1,'a',3,'c'>,<1,'a',4,'d'>,<2,'b',3,'c'>,<2,'b',4,'d'>}