Replace separate PRIM_ERROR and PRIM_RUN_FIBER return codes with a unified PRIM_FIBER in PrimitiveResult enum, updating all primitive implementations and the interpreter switch case to use the new combined value.
Refactor runtime error handling to store errors directly in the fiber's error field instead of on the stack, enabling any object (except null) as an error value. Add Fiber.transferError(_) primitive for transferring errors between fibers. Update validation helpers to accept Value arguments directly and modify RETURN_ERROR macro to set fiber error. Adjust GC marking to use wrenMarkValue for the error field. Add tests for aborting with non-string errors and null abort behavior.
Add a `WrenWriteFn` callback to `WrenConfiguration` that allows host applications to control how text from `System.print()` and related functions is displayed. When set, the VM invokes this callback instead of directly calling `printf`. If the callback is NULL, printed text is silently discarded. The CLI's `initVM()` now registers a simple `write` function that prints to stdout, while the core `system_writeString` primitive checks for the callback before outputting. This change also refactors `wrenInitConfiguration` to set `defaultReallocate` as the default reallocation function and consolidates configuration fields into a single `WrenConfiguration` struct stored directly in `WrenVM`, removing separate member fields for reallocate, bindForeignMethod, bindForeignClass, loadModule, minNextGC, and heapScalePercent.
- Delete wren_io.c, wren_io.h, and io.wren source files
- Remove multi-arity print overloads and IO.read/IO.time methods
- Add System class with print, printAll, write, writeAll methods to core.wren
- Update all documentation examples and README to use System.print instead of IO.print
Replace the manually embedded C string constants for builtin Wren modules with
a new build system that automatically generates `.wren.inc` header files from
`.wren` source files. The old `script/generate_builtins.py` is removed and
replaced by `script/wren_to_c_string.py`, which produces standalone include
files with a `PREAMBLE` containing the module name and source path. The Makefile
gains pattern rules to rebuild these `.wren.inc` files whenever the
corresponding `.wren` source changes, and the `builtin` phony target is removed
since the generation is now automatic. The `wren.mk` wildcard lists are updated
to include the new `.wren.inc` files as dependencies. The `timer.c` and
`wren_core.c` source files now `#include` their respective `.wren.inc` headers
instead of defining the string literals inline, and the `timer.wren` trailing
newline is removed.
The string class is now documented as an immutable byte array rather than a
sequence of Unicode code points. The .count getter is removed from the string
primitive and replaced by .codePoints.count on the code point sequence
interface, making the O(n) cost explicit. Updated the doc site and test files
accordingly.
Extract codePointAt() logic into a dedicated StringCodePointSequence class that wraps a string and implements the Sequence interface, enabling iteration over code points. Add a `codePoints` getter to String that returns a new instance of this sequence. Refactor the underlying C implementation of `codePointAt_` to decode UTF-8 into actual code point integers (returning raw bytes for invalid sequences) and rename the primitive to use trailing underscore convention. Update all related tests to reflect the new behavior where mid-sequence byte indices return the raw byte string instead of an empty string, and add new test files for the code point sequence iteration.
Remove the public `byteAt(_)` method from String and its ByteSequence wrapper, renaming it to the private `byteAt_(_)` to eliminate redundancy with `.bytes[_]`. Add a native `byteCount_` primitive on String and expose it as `count` on StringByteSequence, enabling O(1) byte length queries. Update all test files to use the new `.bytes` subscript API and add a dedicated `count.wren` test for the new functionality.
Add wrenNewStringFromRange function to wren_value.c that decodes UTF-8 code points from source string and re-encodes them into result, enabling correct range subscripts on multi-byte characters. Rename wrenUtf8NumBytes to wrenUtf8EncodeNumBytes and make wrenUtf8Encode return written byte count for use in range construction. Add wrenUtf8DecodeNumBytes utility to skip continuation bytes when iterating by byte index. Remove all skip directives from test files and add UTF-8 specific test cases verifying correct slicing across code point boundaries.
The compiler no longer auto-generates a default `new()` constructor for classes. All classes must now explicitly define `construct new() {}` to be instantiable. This change removes the `createDefaultConstructor` function from the compiler, eliminates the `return_this` primitive used by Object's default initializer, and adds explicit constructors to all test and example classes. Core metaclasses (Bool, Class, Null, Num, Object, Range, Sequence) now correctly reject `new()` calls with runtime errors.
Remove the run() method from fibers and introduce transfer() for non-stack-based fiber switching, along with suspend() to pause the interpreter and return control to the host application. Update Timer.sleep() to use runNextScheduled_() instead of Fiber.yield(), and add Timer.schedule() for creating independently scheduled fibers. Refactor the core fiber runtime to support transfer semantics, including proper error handling for aborted fibers and self-transfer edge cases. Fix a missing quote in test.py's runtime error validation string.
Rename the constructor initializer signature prefix from "this " to "init " in
wren_common.h's MAX_METHOD_SIGNATURE calculation, wren_compiler.c's
signatureToString and createDefaultConstructor functions, and wren_core.c's
default Object constructor primitive registration. This changes the syntactic
keyword used to define initializer methods in the Wren language.
Refactor wrenFindVariable to accept an explicit ObjModule* parameter instead of
implicitly using the main module. Promote the internal getCoreModule helper to
a public wrenGetCoreModule function declared in wren_vm.h. Update all call sites
in wren_core.c and wren_meta.c to pass the core module when looking up core
variables, and replace inline getCoreModule calls in wren_vm.c with the new
public function. Remove the NULL-module fallback documentation from
wrenDeclareVariable and wrenDefineVariable.
Add TOKEN_CONSTRUCT as a new reserved word in the Wren compiler lexer and parser, and update the grammar rule table so that 'construct' triggers a constructor signature instead of 'this'. Modify all built-in class definitions in core.wren, wren_core.c, benchmark files, and test fixtures to use 'construct new(...)' and 'construct named(...)' syntax. Update documentation in classes.markdown and syntax.markdown to reflect the new keyword, and remove the deprecated test files for 'new' and infix class expressions.
Replace all uses of the `new` reserved word with explicit `this new()` constructor definitions and `ClassName.new()` instantiation calls in builtin/core.wren. Update all documentation files (classes.markdown, fiber.markdown, fn.markdown, sequence.markdown, error-handling.markdown, expressions.markdown, fibers.markdown, functions.markdown) to reflect the new constructor syntax, removing `new` keyword examples and replacing them with `ClassName.new()` patterns and `this new()` definitions.
Extract the common pattern of returning the receiver argument into a single
DEF_PRIMITIVE(return_this) function, and refactor fiber_instantiate,
fn_instantiate, and the default Object constructor to use it instead of
inline RETURN_VAL(args[0]) calls. Also fix trailing whitespace on isEmpty
and class_toString lines in the core library source string.
Extract class name retrieval from object_toString into a new class_toString primitive, registered on the Class metaclass. This removes the IS_CLASS branch from object_toString, which now only handles instances and falls back to "<object>". The change ensures Class objects return their own name directly via toString rather than relying on the generic object handler.
The safeToString_ mechanism introduced in 40897f33 used per-fiber maps and lists to detect recursive toString calls, but leaked memory when runtime errors occurred before cleanup. This reverts to direct toString implementations for List and Map, removing the recursive detection logic and updating tests to mark self-referencing containers as TODO.
Add `String.safeToString_` static method that tracks objects currently being
converted to string per fiber, returning "..." when recursion is detected.
Wrap List.toString and Map.toString with this guard to handle self-referential
and mutually recursive structures without crashing.
Introduce a new static method `Object.same(obj1, obj2)` that exposes the VM's
built-in equality semantics (`wrenValuesEqual`) directly, bypassing any
user-defined `==` overrides. This required creating a dedicated metaclass for
Object (subclass of Class) to host the static method without polluting every
class with a `same` method. The implementation wires up a new `Object metaclass`
in the core initialization sequence, adjusts the class hierarchy setup order,
and adds comprehensive tests covering value types, identity comparison, and
verification that `Object.same` ignores custom `==` operators.
The static helper `callFunction` in wren_core.c was renamed to `callFn` to prevent symbol conflicts with the public `wrenCallFunction` API, ensuring unique linkage and clearer separation between internal and external call paths.
The `.list` method on Sequence was renamed to `.toList` to better reflect its
purpose of converting a sequence into a List object. This change updates the
method definition in `builtin/core.wren` and `src/vm/wren_core.c`, along with
all test files that called `.list` on sequences, maps, ranges, and custom
sequence implementations. The test file `test/core/sequence/list.wren` was also
renamed to `test/core/sequence/to_list.wren` to match the new method name.
Move the definitions of Bool, Fiber, Fn, Null, and Num classes from hardcoded C code in wren_core.c into the core.wren library source, allowing them to be parsed and created during library initialization. Simplify defineClass to always use wrenNewSingleClass, remove redundant root pushing in wrenNewClass, and adjust the class creation in the interpreter to use a Value instead of ObjClass*.
Consolidate the refactoring branch changes from patriciomacadden's fork into the main repository, incorporating the updated class definition logic in wren_core.c that replaces the separate defineSingleClass function with a unified defineClass function capable of handling both raw and subclassed class creation.
Refactor Sequence.map and Sequence.where to return lazy MapSequence and WhereSequence wrappers instead of eagerly building a List. Add new MapSequence and WhereSequence classes that delegate iteration and apply the transformation or predicate on-the-fly. Update documentation to reflect lazy semantics and the need to call .list to materialize results. Adjust all existing tests to call .list on map/where results. Add new tests in test/core/sequence/ verifying lazy behavior with infinite Fibonacci iterators.
Add a new `each` method to the Sequence class in the Wren programming language,
allowing iteration over sequence elements by passing each element to a provided
function. This replaces the previous pattern of using `map` with `Fiber.yield`
in examples, providing a more direct and idiomatic way to perform side effects
per element. The implementation includes a core library method in `core.wren`,
a C source string in `wren_core.c`, documentation in the Sequence markdown file,
and three test cases covering normal iteration, empty sequences, and non-function
argument error handling.
The defineSingleClass helper was only used for the initial Object and Class
definitions during core initialization. By inlining its logic into defineClass
with a check for vm->classClass being NULL, we eliminate a redundant function
while preserving the same behavior for those two special cases.
Introduce MapSequence and WhereSequence subclasses of Sequence that apply transformations lazily during iteration instead of building intermediate lists. Update Sequence.map and Sequence.where to return these deferred wrappers, modify all existing tests to call .list on results, and add new infinite-sequence tests verifying lazy behavior on Fibonacci iterators.
Add a new `each` method to the Sequence class that iterates over elements
calling a provided function for each, serving as a side-effect-only
alternative to `map` when the resulting list is not needed. This is
particularly important for the upcoming change where `map` will return a
new sequence instead of mutating in place, as demonstrated by updating
the README and index examples to use `each` with Fiber.yield. Includes
documentation in the Sequence API reference and three new test cases
covering normal iteration, empty sequences, and non-function argument
error handling.
Rewrite all() and any() to store and return the predicate's result directly, matching && and || semantics. Update documentation to describe the new behavior. Move tests from test/core/list/ to test/core/sequence/ and add cases verifying that the first falsey/truthy value is returned.
Implements a new `list` method on the Sequence class that iterates over all elements and returns them as a freshly created List object. Includes documentation with usage example and a test case using a custom TestSequence class to verify correct behavior.
Add `byteAt(index)`, `codePointAt(index)`, and `bytes` sequence to String,
enabling direct byte-level manipulation of UTF-8 encoded strings. Introduce
`\x` hex escape sequence in string literals for specifying raw byte values.
Refactor Unicode escape parsing into a generic `readHexEscape` function
supporting variable digit counts. Implement `wrenUtf8Decode` utility for
decoding UTF-8 sequences from byte buffers. Add comprehensive tests for
`byteAt` including boundary conditions and error cases.
Implements a new `list` method on the Sequence class that iterates over all elements and collects them into a new List instance. Includes documentation in the core sequence docs and a test case verifying correct behavior with a custom sequence implementation.
Implement the `String.fromCodePoint(_)` primitive that creates a string from a Unicode code point, with validation for integer range 0–0x10ffff. Extract inline UTF-8 encoding logic from `readUnicodeEscape` in the compiler into new `wrenUtf8NumBytes` and `wrenUtf8Encode` utility functions in `wren_utils`, and add `wrenStringFromCodePoint` helper in `wren_value`. Update documentation for core classes to add "Methods" and "Static Methods" section headers, and include `String.fromCodePoint` docs with example. Add a test file `from_code_point.wren` covering various code points.
Implement a new `count(f)` method on the Sequence class that iterates over elements and returns the number of items for which the given predicate function evaluates to true. Update the core library source, sequence documentation, and add three new test files covering normal usage, non-boolean return values, and non-function argument error handling. Also fix minor terminology in list docs (items → elements).
Remove the `WrenVM* vm` parameter from `wrenValueBufferInit`, `wrenByteBufferInit`,
`wrenIntBufferInit`, `wrenStringBufferInit`, `wrenSymbolTableInit`,
`wrenMethodBufferInit`, `wrenStringFind`, and `wrenDebugPrintStackTrace`
functions across the compiler, core, debug, utils, value, and VM modules.
Update all call sites and macro definitions to match the simplified signatures,
eliminating dead parameters that were never used within the function bodies.
Replace the hand-rolled capacity/count/elements fields in ObjList with a
ValueBuffer struct, and update Compiler to use a ValueBuffer for its
constant pool instead of an ObjList. This eliminates the separate
ensureListCapacity and wrenListAdd functions, centralizing buffer growth
logic in wrenValueBufferWrite. Adjust all list primitives (add, clear,
count, iterate, iteratorValue) and the GC marking path to operate on the
embedded ValueBuffer. Add wrenMarkBuffer helper for marking buffer
contents during sweep.
Consolidate temporary variable usage in list_add, list_count, and list_iterate by directly inlining AS_LIST/AS_NUM calls. Remove the entire block of num_abs, num_acos, num_asin, num_atan, num_atan2, num_ceil, num_cos, num_floor, and num_fraction primitive definitions to eliminate boilerplate.
Add acos, asin, atan, atan2, tan methods to Num class and expose Num.pi constant with value π. Include corresponding C primitives in wren_core.c and test files for each new method.
Convert `validateIndexValue` and `validateIndex` return types to `uint32_t` with `UINT32_MAX` sentinel, update `wrenNewList`, `wrenListInsert`, `wrenListRemoveAt` signatures, and remove the TODO comment about type unification with `ObjMap`.
