Constrains list Vars to integers in the eplex instance EplexInstance. If a variable in Vars is not already a problem variable for EplexInstance, it will be added as a new problem variable. The external solver will then take the integrality into account, i.e. to solve a MIP/MIQP rather than a relaxed LP/QP problem. Unlike integers/1 constraints from other solvers, the variables are not constrained to be integer type at the ECLiPSe level. However, when a typed_solution is retrieved (e.g. via eplex_var_get/3), this will be rounded to the nearest integer.
Note that even when problem variables have been declared as integers in other solvers (ic or other external solver states), if the integrality constraint is not made known to this EplexInstance, any invocation of the eplex external solver (e.g. via eplex_solve/1) will only solve a continuous relaxation.