ILOG OPL Development Studio Language Reference Manual

Data and decision variable identifiersSince data and decision variable identifiers are the basic components of expressions, we willreview briefly here how they are used to build expressions. If r is a tuple with a fieldcapacity of type T, then r.capacity is an expression of type T. If a is an n-dimensionalarray of type T, a[e 1 ]...[e n] is an expression of type T, provided that e i is well-typed.For instance, the excerptint limit[routes] = ...;dvar int transp[r in routes] in 0..limit[r];contains an expression limit[r] of type integer. Indices of arrays can be complexexpressions. For instance, the excerptint nbFlights = ...;range Flight = 1..nbFlights;{string} Employee = ...;dvar int crew[Flight][Employee] in 0..1;constraints {}forall(e in Employee)forall(i in 1..nbFlights - 2)crew[i][e] + crew[i+1][e] + crew[i+2][e] >= 1;contains an integer expression crew[i+1][e] whose first index is itself an integerexpression.I L O G O P L D E V E L O P M E N T S T U D I O L A N G U A G ER E F E R E N C E M A N U A L91