* ch-exp.y (value_string_element, string_primitive_value,
start_element, left_element, right_element, slice_size,
lower_element, upper_element, first_element): Removed.
(value_string_slice, value_array_slice): Replaced by ...
(slice): New non-terminal, with working slice support.
(primitive_value_lparen, rparen): New non-terminals.
(maybe_tuple_elements): New non-terminal, to allow empty tuples.
(idtokentab): Added "up".
* value.h (COERCE_VARYING_ARRAY): New macro.
* valarith.c (value_subscript): Use it.
* valops.c (value_cast): Likewise. Also, do nothing if already
correct type, and allow converting from/to range to/from scalar.
* valops.c, value.h (varying_to_slice, value_slice): New functions.
* eval.c (OP_ARRAY): Add cast for array element.
* expression.h (TERNOP_SLICE, TERNOP_SLICE_COUNT): New exp_opcodes.
* valops.c (chill_varying_type): Moved function frp, here ...
* gdbtypes.c (chill_varying_type), gdbtypes.h: ... to here.
* parse.c (length_of_subexp, prefixify_subexp): Add support
for TERNOP_SLICE, TERNOP_SLICE_COUNT.
* expprint.c (print_subexp, dump_expression): Likewise.
* eval.c (evaluate_subexp): Likewise.
* eval.c (evaluate_subexp case MULTI_SUBSCRIPT): Don't call
value_x_binop on a Chill varying string.