Ordering indices

Especially when working with sparse arrays, the sequence of their indices in loops should correspond as far as possible to the sequence given in their declaration. For example an array of variables declared by:

 declarations
  A,B,C: range
  x: array(A,B,C) of mpvar
 end-initializations

that is mostly used in expressions like sum(b in B, c in C, a in A) x(a,b,c) should preferrably be declared as

 declarations
  A,B,C: range
  x: array(B,C,A) of mpvar
 end-declarations

or alternatively the indices of the loops adapted to the order of indices of the variables.