Sets implies

Hi,
   I have a problem understanding why the following piece of code doesn't work. I am using eclipse 5.6 #42.

use_module(library(conjunto)) .
spy #=>
Var::[1, 2, 3, 4], Tmp `:: {} .. {one, two, three}, #(Tmp, 2), ((Var #= 2) #=> (two in Tmp)), Var #= 2 .

Following is the trace 
  (3) 3 CALL    VAR :: 1..4
  (3) 3 EXIT    VAR{1..4]} :: 1..4
 (4) 1 CALL    Tmp `:: {} .. {one, ..., ...}
 (4) 1 EXIT    Tmp{{} .. {..., ...}} `:: {} .. {one, ..., ...}
 (6) 1 CALL    #(Tmp{{} .. {..., ...}}, 2)
 (6) 1 EXIT    #(Tmp{{} .. {..., ...}}, 2)
+(14) 1 CALL    Var{[... .. ...]}#=2 #=> one in Tmp{{} .. {...}}
  (15) 2 CALL    #=(Var{1..4]}, 2, _22185{[0, 1]})
   (17) 4 CALL    unify_set(_22185{[0, 1]}, _82815)
   (17) 4 EXIT    unify_set(_22185{[0, 1]}, _82815)
   (21) 4 CALL    wake
   (21) 4 EXIT    wake
  (22) 3 DELAY<3>    #=(Var{1..4]}, 2, _22185{[0, 1]})
 (15) 2 EXIT    #=(Var{1..4]}, 2, _22185{[0, 1]})
+(14) 1 FAIL    ... #=> ...

I would really appreciate if any one can throw some light on this problem.
Thank you

Note: I have to use conjunto.

Ponnu