nl_tokens: This is part of the old simple - minded splice . We are using it either because the receiver is not an array ( so we have no choice ) or because we know we are not deleting or moving a lot of elements .
pl_tokens: function SimpleSlice ( array , start_i , del_count , len , deleted_elements ) { for ( var i = 0 ; i < del_count ; i ++ ) { var index = start_i + i ; if ( index in array ) { var <mask> = array [ index ] ; % CreateDataProperty ( deleted_elements , i , current ) ; } } }