This is a breaking change because existing imports in user Wren code
that assume the path is relative to the entrypoint file will now likely
fail.
Also, stack trace output and host API calls that take a module string
now need the resolved module string, not the short name that appears in
the import.
Guesses whether the input is an expression or statement and handles it
appropriately. Finally, after over a year, the Wren REPL automatically
prints "3" if you type in "1 + 2". \o/
This allows "%(...)" inside a string literal to interpolate the
stringified result of an expression.
It doesn't support custom interpolators or format strings, but we can
consider extending that later.
- Make sure it handles an empty gray set.
- Make sure growing the gray stack doesn't itself trigger a GC.
- Make sure it works when stress testing is enabled.
- Ensure the tests kick off a GC.
The previous GC implementation used a recursive mark method. This can
result in stack overflows when attempting to mark deeply nested objects.
This commit replaces the recursive approach with an iteritive one,
moving the state stack from the C call stack to the `WrenVM` structure.
As objects are 'grayed' they are pushed onto the VM's gray stack. When
we have grayed all of the root objects we iterate until the stack is
empty graying any obejcts which haven't been marked as dark before. At
the end of the process we clean up all unmarked objects as before.
This commit also adds a few new tests which check garbage collection by
allocating some new deeply nested objects and triggering the GC a few
times in the process.
Get rid of the separate opt-in IO class and replace it with a core
System class.
- Remove wren_io.c, wren_io.h, and io.wren.
- Remove the flags that disable it.
- Remove the overloads for print() with different arity. (It was an
experiment, but I don't think it's that useful.)
- Remove IO.read(). That will reappear using libuv in the CLI at some
point.
- Remove IO.time. Doesn't seem to have been used.
- Update all of the tests, docs, etc.
I'm sorry for all the breakage this causes, but I think "System" is a
better name for this class (it makes it natural to add things like
"System.gc()") and frees up "IO" for referring to the CLI's IO module.
Most of the pieces are there:
- You can declare a foreign class.
- It will call your C function to provide an allocator function.
- Whenever a foreign object is created, it calls the allocator.
- Foreign methods can access the foreign bytes of an object.
- Most of the runtime checking is in place for things like subclassing
foreign classes.
There is still some loose ends to tie up:
- Finalizers are not called.
- Some of the error-handling could be better.
- The GC doesn't track how much memory a marked foreign object uses.
* Eliminate "new" reserved word.
* Allow "this" before a method definition to define a constructor.
* Only create a default constructor for classes that don't define one.
If a test expected an error and found at least one, it would not fail
on any other expected errors that didn't occur.
Also, some tests were expecting a compile time error message even though
the test script doesn't validate those (yet).
The test function was getting monolithic, so I went ahead and split it
into a separate little class.
- "\x" escape sequence to put byte values in strings: "\x34"
- String.byteAt(index) gets value of byte in string.
- String.bytes returns a raw sequence of bytes for a string.
- String.codePointAt(index) gets the code point at an offset as a raw number.
