Add `for (variable in sequence)` syntax to the Wren language, introducing the `in` keyword token and compiler support for iterating over sequences using `iterate` and `iteratorValue` methods. Includes new benchmark files for Lua, Python, Ruby, and Wren, plus test cases covering single-expression bodies, block bodies, closures over loop variables, and break statements. Also fixes a missing POP() in CLOSE_UPVALUE and moves the while test file to a subdirectory.
- Remove two TODO comments in wren_compiler.c about parameter length overflow check and assignment in named call
- Remove TODO about interning bool_toString and null_toString strings in wren_core.c
- Replace oversized 100-char temp buffer with precise 21-char buffer in num_toString, referencing Lua implementation
- Rename io_write native to io_writeString and remove TODO about calling toString on argument
Refactor the VM's fiber representation from a stack-allocated `Fiber` struct embedded in `WrenVM` to a full `ObjFiber` object managed by the garbage collector. This includes adding the `OBJ_FIBER` object type enum, a `wrenNewFiber` allocation function, a `markFiber` traversal routine for GC marking, and updating all internal APIs (`DEF_FIBER_NATIVE`, `wrenDebugDumpStack`) to use `ObjFiber*` instead of `Fiber*`. The `Fiber` struct definition and its associated `CallFrame` type are moved from `wren_vm.h` into `wren_value.h`, and the `STACK_SIZE`/`MAX_CALL_FRAMES` constants are relocated accordingly. Additionally, the `vm->fiber` singleton pointer is removed, the `vm->unsupported` sentinel value is eliminated (replaced by returning `NULL_VAL` for invalid numeric operands), and the `wrenInterpret` function is temporarily removed. The `wrenNewClass` function's metaclass pinning order is also corrected to prevent premature GC collection.
The bootstrapping of Object and Class now uses a two-phase approach: first creating a raw class with no metaclass or superclass via wrenNewSingleClass, then explicitly wiring superclass relationships with wrenBindSuperclass. This eliminates the need for special-case handling of null superclasses in the old newClass function and makes the metaclass chain setup explicit in wrenInitializeCore.
Replace the global `io` singleton object with a static `IO` class, moving the `write` native from the instance to the metaclass. Update all benchmark, example, and test files to use `IO.write()` instead of `io.write()`.
Implement list subscript setter (`[ ]=`) native method in wren_core.c, enabling assignment to list elements via bracket syntax. Extract duplicate parameter count validation logic into a shared `validateNumParameters` function in wren_compiler.c, replacing inline checks in both `parameterList` and `methodCall`. Add comprehensive test suite covering basic assignment, return value semantics, negative indices, and error cases for out-of-range and excessive arguments.
Remove the `this new` constructor declaration syntax in favor of a `new` keyword that creates instances directly. Superclass constructors are now invoked via bare `super(args)` instead of `super.new(args)`, eliminating the semantic weirdness of calling a constructor on a partially-constructed instance. Update the compiler to treat `new` as a keyword token, replace the `isMethod` flag with `methodName`/`methodLength` fields, and change the VM's `NEW` opcode to pop the class from the stack before creating the instance. Add a default `new` native method on Object that returns `this`. Update all benchmarks and tests to use the new syntax.
Remove "(bob)" author prefix from all TODO comments in benchmark/method_call.wren, include/wren.h, src/main.c, src/wren_common.h, src/wren_compiler.c, src/wren_core.c, src/wren_value.c, src/wren_value.h, and src/wren_vm.c. Update the TODO_PATTERN regex in metrics script to match the new format without author parentheses. Also refactor test file counting in metrics to use os.walk with fnmatch for recursive directory traversal instead of glob.iglob.
The old code subtracted oldSize from totalAllocated during deallocation,
which required knowing the object size at free time. This was unsafe
because it could read a freed object to determine its size. The new
approach tracks bytesAllocated by only adding new allocations and
relying on GC marking to account for freed memory, making it both
correct and faster with less code.
Add TOKEN_TILDE token type and lexer support for the '~' character in the compiler. Implement the bitwise NOT operation as a native method on the Num class, operating on 32-bit unsigned integers. Include a new OPERATOR macro for prefix/infix operator grammar rules and add comprehensive test cases covering positive, negative, floating-point, and boundary values.
Add closure objects that wrap functions with captured upvalues, enabling
first-class closures that close over local variables from enclosing scopes.
Introduce new bytecode instructions (CODE_CLOSURE, CODE_LOAD_UPVALUE,
CODE_STORE_UPVALUE, CODE_CLOSE_UPVALUE, CODE_RETURN) and a CompilerUpvalue
tracking system with a MAX_UPVALUES limit of 256. Refactor the grammar to
strictly separate statements from expressions, fixing a bug where block
expressions incorrectly popped locals while temporaries remained on the
stack. Rename internal functions (wrenCallFunction, wrenDebugDumpInstruction,
wrenDebugDumpStack) and add Upvalue allocation, closure creation, and
debug dump support for the new instructions.
Add MAX_PARAMETERS constant set to 16 and extend VM bytecode instructions CODE_CALL_11 through CODE_CALL_16 to support the new limit. Introduce compile-time error messages when parameter or argument count exceeds 16 in function definitions, method declarations, subscript calls, and regular method calls. Add new native fiber call stubs fn_call9 through fn_call16 and register them in the core initialization. Include comprehensive test coverage for 9-16 parameter functions and methods, plus error tests for exceeding the limit in all contexts.
Rename the `primitives.h` and `primitives.c` files to `wren_core.h` and `wren_core.c` respectively, reflecting the module's purpose of defining built-in classes and native methods. Update all includes, macro names (PRIMITIVE -> NATIVE, DEF_PRIMITIVE -> DEF_NATIVE, etc.), and function calls (wrenLoadCore -> wrenInitializeCore) across the codebase and Xcode project file to match the new naming convention.
