FZN syntax error triggered by opt/where

[wldhx]

Hi, here's a repro:

set of int: S = 0..9;

array[S] of var opt S: x_inv;
array[S] of var set of int: x_roff =
    array1d(S,
    [ let { var opt S: s = x_inv[l]; } % trigger (1): opt
      in if occurs(s)
         then {deopt(s)}
         else {}
         endif
    | l in S ]);
array[S] of var set of int: x_occupancy =
    array1d(S,
    [ { r  
      | r in x_roff[l]
        where r <= l } % trigger (2): where
    | l in S ]);

This yields

Error: Unknown character in line no. 78
Error: syntax error, unexpected FZ_ID, expecting FZ_INT_LIT or FZ_INT or '{' in line no. 78
=====ERROR=====

Either removing the where clause or changing the variable to non-opt solves the problem.

The offending FZN line is

var set of -infinity..infinity: X_INTRODUCED_273_ ::var_is_introduced ;

---

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MiniZinc to FlatZinc converter, version 2.8.2
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