Title: Variable name exists
Goal: Reject merging the instances of the expression `X+2' to `Pid'.
Parameters:
    [   {file,"ref_edenypid2.erl"},
        {posrange,{59,61}},
        {varname,"Pid"} ].
Documentation:
 The expression cannot be bound to `Pid',
 because the name `Pid' is already bound in the scope of the expression.

