gap> f := function()
>     return 1 - "abc";
> end;
function(  ) ... end
gap> f();
Error, no method found! For debugging hints type ?Recovery from NoMethodFound
Error, no 1st choice method found for `AdditiveInverseMutable' on 1 arguments at GAPROOT/lib/methsel2.g:249 called from
AINV_MUT( elm ) at GAPROOT/lib/arith.gi:201 called from
AdditiveInverseAttr( elm ) at GAPROOT/lib/arith.gi:214 called from
1 - "abc" at *stdin*:3 called from
<function "f">( <arguments> )
 called from read-eval loop at *stdin*:5
type 'quit;' to quit to outer loop
brk> QUIT;
