Example breaking InversesOfSemigroupElement

[ChristopherRussell]

gap> S := Monoid( [ Transformation( [ 1, 2, 4, 4 ] ), Transformation( [ 4, 2, 3, 4 ] ),
>   Transformation( [ 1, 4, 3, 4 ] ) ] );;
gap> IsEUnitaryInverseSemigroup(S);
Error, List Element: <list>[1] must have an assigned value in
  y := InversesOfSemigroupElement( S, x )[1]; at /Users/crussell/gap/lib/semipperm.gi:339 called from
func( C[i] ) at /Users/crussell/gap/lib/coll.gi:746 called from
List( GeneratorsOfSemigroup( S ), iso ) at /Users/crussell/gap/lib/semipperm.gi:344 called from
IsomorphismPartialPermSemigroup( S
 ) at /Users/crussell/gap/pkg/semigroups/gap/semigroups/semigrp.gi:1281 called from
AsSemigroup( IsPartialPermSemigroup, S
 ) at /Users/crussell/gap/pkg/semigroups/gap/attributes/properties.gi:343 called from
<compiled or corrupted statement>  called from
...  at *stdin*:27
you can 'return;' after assigning a value