My GAP version is 4.6.5. When I performed the command "IsIdentical( 1, 1 );" (this is an example in the section 27.10 of the manual ), it can not work. The information of error is gap> IsIdentical( 1, 1 ); Error, Variable: 'IsIdentical' must have a value not in any function at line 1 of *stdin* Thank for reading.