When calling `mrb_equal()` or `mrb_funcall()` family functions, the GC arena should be restored if the loop is repeated by a non-immediate return value.
In my opinion, restoring the GC arena is unnecessary when a non-immediate (true) value causes the function to return (e.g. the `mrb_ary_index_m()` function).
The patch does not take into account the case of recursive calls and may be incomplete.
Internal functions can only be called from within the library.
Functions listed in `mruby/internal.h` can be called from:
* core (src/*.c)
* gems (mrbgems/**/*.c)
But not from the application linked with `libmruby`.
- Added to `mruby-binding-core`
- `Binding#local_variable_defined?`
- `Binding#local_variable_get`
- `Binding#local_variable_set`
- `Binding#local_variables`
- `Binding#receiver`
- `Binding#source_location`
- `Binding#inspect`
- Added to `mruby-proc-binding`
- `Proc#binding`
The reason for separating `Proc#binding` is that core-mrbgems has a method that returns a closure object to minimize possible problems with being able to manipulate internal variables.
By separating it as different mrbgem, each user can judge this problem and incorporate it arbitrarily.
Instead of including `mruby/presym.h` everywhere, we provided the
fallback `mruby/presym.inc` under `include/mruby` directory, and specify
`-I<build-dir>/include` before `-I<top-dir>/include` in `presym.rake`.
So even when someone drops `-I<build-dir>/include` in compiler options,
it just compiles without failure.
Integrate the implementation with `Module#define_method`.
- Introduce the internal function `mrb_mod_define_method_m()` (no static)
- The `Object#define_singleton_method` method can now accept a second argument
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).
They are basically the copy of instance variable tables. On my Linux
box, memory consumption of `mrbtest` measured by `valgrind` is:
- old: 17,683,830 bytes
- new: 14,283,749 bytes
If `#methods` traverse the super class, it includes the methods that
were does `undef` in the subclass.
Before patched:
```terminal
% bin/mruby -e 'p Module.instance_methods - Class.instance_methods'
[]
```
After patched:
```terminal
% bin/mruby -e 'p Module.instance_methods - Class.instance_methods'
[:append_features, :extend_object]
```
The binary sizes (gems are only `mruby-bin-mruby`) are reduced slightly in
my environment than before the introduction of new specifiers/modifiers
(5116789a) with this change.
------------+-------------------+-------------------+--------
BINARY | BEFORE (5116789a) | AFTER (This PR) | RATIO
------------+-------------------+-------------------+--------
mruby | 593416 bytes | 593208 bytes | -0.04%
libmruby.a | 769048 bytes | 767264 bytes | -0.23%
------------+-------------------+-------------------+--------
BTW, I accidentally changed `tasks/toolchains/visualcpp.rake` at #4613,
so I put it back.