The "a"/"*" specifier of the `mrb_get_args()` function will now return `const mrb_value *`.
This is because it is difficult for the caller to check if it is an array object and write-barrier if necessary.
And it requires calling `mrb_ary_modify()` on the unmodified array object, which is also difficult (this is similar to #5087).
src/hash.c:
- mrb_hash_(aget|aset|dup|delete): internal linkage
- remove documentation of methods which are not implemented (in here)
- remove #assoc; unused, not in ISO spec
- remove #rassoc: same, implementation is also wrong
hash-ext mrbgem:
- remove header "mruby/khash.h"
- remove mrb_hash_values_at (move code into hash_values_at, i: long -> int)
- less whitespace in gem_init function
- reduce compile time by a little bit (full-core: ~0.7s for me)
- thanks to 'include-what-you-use' for some help
- include Standard C header files before any other (coding style)
Yukihiro "Matz" Matsumoto